let f be non constant standard special_circular_sequence; for i1, j1, i2, j2 being Element of NAT st i1 <= len (GoB f) & j1 <= width (GoB f) & i2 <= len (GoB f) & j2 <= width (GoB f) & ( j2 = j1 + 1 or j1 = j2 + 1 ) & i1 = i2 & Int (cell (GoB f),i1,j1) c= (LeftComp f) \/ (RightComp f) holds
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)
let i1, j1, i2, j2 be Element of NAT ; ( i1 <= len (GoB f) & j1 <= width (GoB f) & i2 <= len (GoB f) & j2 <= width (GoB f) & ( j2 = j1 + 1 or j1 = j2 + 1 ) & i1 = i2 & Int (cell (GoB f),i1,j1) c= (LeftComp f) \/ (RightComp f) implies Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f) )
assume that
A1:
i1 <= len (GoB f)
and
A2:
j1 <= width (GoB f)
and
A3:
i2 <= len (GoB f)
and
A4:
j2 <= width (GoB f)
and
A5:
( j2 = j1 + 1 or j1 = j2 + 1 )
and
A6:
i1 = i2
; ( not Int (cell (GoB f),i1,j1) c= (LeftComp f) \/ (RightComp f) or Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f) )
now assume A7:
Int (cell (GoB f),i1,j1) c= (LeftComp f) \/ (RightComp f)
;
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)now per cases
( j2 = j1 + 1 or j1 = j2 + 1 )
by A5;
case A8:
j2 = j1 + 1
;
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)now per cases
( ex k being Element of NAT st
( 1 <= k & k + 1 <= len f & i2 <> 0 & i2 <> len (GoB f) & LSeg (f /. k),(f /. (k + 1)) = LSeg ((GoB f) * i2,(j1 + 1)),((GoB f) * (i2 + 1),(j1 + 1)) ) or for k being Element of NAT holds
( not 1 <= k or not k + 1 <= len f or not i2 <> 0 or not i2 <> len (GoB f) or not LSeg (f /. k),(f /. (k + 1)) = LSeg ((GoB f) * i2,(j1 + 1)),((GoB f) * (i2 + 1),(j1 + 1)) ) )
;
case
ex
k being
Element of
NAT st
( 1
<= k &
k + 1
<= len f &
i2 <> 0 &
i2 <> len (GoB f) &
LSeg (f /. k),
(f /. (k + 1)) = LSeg ((GoB f) * i2,(j1 + 1)),
((GoB f) * (i2 + 1),(j1 + 1)) )
;
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)then consider k being
Element of
NAT such that A9:
( 1
<= k &
k + 1
<= len f )
and A10:
i2 <> 0
and A11:
i2 <> len (GoB f)
and A12:
LSeg (f /. k),
(f /. (k + 1)) = LSeg ((GoB f) * i2,(j1 + 1)),
((GoB f) * (i2 + 1),(j1 + 1))
;
now per cases
( ( f /. k = (GoB f) * i2,(j1 + 1) & f /. (k + 1) = (GoB f) * (i2 + 1),(j1 + 1) ) or ( f /. k = (GoB f) * (i2 + 1),(j1 + 1) & f /. (k + 1) = (GoB f) * i2,(j1 + 1) ) )
by A12, SPPOL_1:25;
case A13:
(
f /. k = (GoB f) * i2,
(j1 + 1) &
f /. (k + 1) = (GoB f) * (i2 + 1),
(j1 + 1) )
;
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)A14:
(
Int (left_cell f,k) c= LeftComp f &
LeftComp f c= (LeftComp f) \/ (RightComp f) )
by A9, GOBOARD9:24, XBOOLE_1:7;
i2 < len (GoB f)
by A3, A11, XXREAL_0:1;
then A15:
i2 + 1
<= len (GoB f)
by NAT_1:13;
0 + 1
<= j1 + 1
by XREAL_1:8;
then A16:
(
Indices (GoB f) = [:(dom (GoB f)),(Seg (width (GoB f))):] &
j1 + 1
in Seg (width (GoB f)) )
by A4, A8, FINSEQ_1:3, MATRIX_1:def 5;
1
<= i2 + 1
by NAT_1:11;
then
i2 + 1
in dom (GoB f)
by A15, FINSEQ_3:27;
then A17:
[(i2 + 1),(j1 + 1)] in Indices (GoB f)
by A16, ZFMISC_1:106;
i2 >= 0 + 1
by A10, NAT_1:13;
then
i2 in dom (GoB f)
by A3, FINSEQ_3:27;
then
[i2,(j1 + 1)] in Indices (GoB f)
by A16, ZFMISC_1:106;
then
left_cell f,
k = cell (GoB f),
i2,
(j1 + 1)
by A9, A13, A17, GOBOARD5:29;
hence
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)
by A14, XBOOLE_1:1;
verum end; case A18:
(
f /. k = (GoB f) * (i2 + 1),
(j1 + 1) &
f /. (k + 1) = (GoB f) * i2,
(j1 + 1) )
;
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)A19:
(
Int (right_cell f,k) c= RightComp f &
RightComp f c= (LeftComp f) \/ (RightComp f) )
by A9, GOBOARD9:28, XBOOLE_1:7;
i2 < len (GoB f)
by A3, A11, XXREAL_0:1;
then A20:
i2 + 1
<= len (GoB f)
by NAT_1:13;
0 + 1
<= j1 + 1
by XREAL_1:8;
then A21:
(
Indices (GoB f) = [:(dom (GoB f)),(Seg (width (GoB f))):] &
j1 + 1
in Seg (width (GoB f)) )
by A4, A8, FINSEQ_1:3, MATRIX_1:def 5;
1
<= i2 + 1
by NAT_1:11;
then
i2 + 1
in dom (GoB f)
by A20, FINSEQ_3:27;
then A22:
[(i2 + 1),(j1 + 1)] in Indices (GoB f)
by A21, ZFMISC_1:106;
i2 >= 0 + 1
by A10, NAT_1:13;
then
i2 in dom (GoB f)
by A3, FINSEQ_3:27;
then
[i2,(j1 + 1)] in Indices (GoB f)
by A21, ZFMISC_1:106;
then
right_cell f,
k = cell (GoB f),
i2,
(j1 + 1)
by A9, A18, A22, GOBOARD5:30;
hence
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)
by A19, XBOOLE_1:1;
verum end; end; end; hence
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)
;
verum end; case A23:
for
k being
Element of
NAT holds
( not 1
<= k or not
k + 1
<= len f or not
i2 <> 0 or not
i2 <> len (GoB f) or not
LSeg (f /. k),
(f /. (k + 1)) = LSeg ((GoB f) * i2,(j1 + 1)),
((GoB f) * (i2 + 1),(j1 + 1)) )
;
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)now per cases
( i2 = 0 or i2 = len (GoB f) or ( i2 <> 0 & i2 <> len (GoB f) & ( for k being Element of NAT holds
( not 1 <= k or not k + 1 <= len f or not LSeg (f /. k),(f /. (k + 1)) = LSeg ((GoB f) * i2,(j1 + 1)),((GoB f) * (i2 + 1),(j1 + 1)) ) ) ) )
by A23;
case A24:
i2 = 0
;
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)reconsider p =
|[((((GoB f) * 1,(j1 + 1)) `1 ) - 1),(((GoB f) * 1,(j1 + 1)) `2 )]| as
Point of
(TOP-REAL 2) ;
A25:
1
< len (GoB f)
by GOBOARD7:34;
A26:
1
< width (GoB f)
by GOBOARD7:35;
reconsider P =
{p} as
Subset of
(TOP-REAL 2) ;
A27:
p `1 < (p `1 ) + 1
by XREAL_1:31;
A28:
1
<= 1
+ j1
by NAT_1:11;
then
((GoB f) * 1,(j1 + 1)) `1 = ((GoB f) * 1,1) `1
by A4, A8, A25, GOBOARD5:3;
then A29:
p `1 = (((GoB f) * 1,1) `1 ) - 1
by EUCLID:56;
p in { |[s,r]| where s, r is Real : s <= ((GoB f) * 1,1) `1 }
then A30:
p in v_strip (GoB f),
i2
by A24, A26, GOBOARD5:11;
( ( for
q being
Point of
(TOP-REAL 2) st
q in P holds
q `1 < ((GoB f) * 1,1) `1 ) implies
P misses L~ f )
by GOBOARD8:21;
then A31:
(
p in {p} &
{p} c= (L~ f) ` )
by A29, A27, SUBSET_1:43, TARSKI:def 1;
then reconsider p1 =
p as
Point of
((TOP-REAL 2) | ((L~ f) ` )) by PRE_TOPC:29;
A32:
(
j1 = 0 or
j1 >= 0 + 1 )
by NAT_1:13;
A33:
now per cases
( ( j1 >= 1 & j1 + 1 < width (GoB f) ) or ( j1 >= 1 & j1 + 1 = width (GoB f) ) or ( j1 = 0 & j1 + 1 < width (GoB f) ) or ( j1 = 0 & j1 + 1 = width (GoB f) ) )
by A4, A8, A32, XXREAL_0:1;
case A34:
(
j1 >= 1 &
j1 + 1
< width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )then A35:
(j1 + 1) + 1
<= width (GoB f)
by NAT_1:13;
A36:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j1 + 1)) `2 <= r & r <= ((GoB f) * 1,((j1 + 1) + 1)) `2 ) }
1
<= j1 + 1
by NAT_1:11;
then
p in h_strip (GoB f),
(j1 + 1)
by A25, A34, A36, GOBOARD5:6;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A30, XBOOLE_0:def 4;
then A37:
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
A38:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j1) `2 <= r & r <= ((GoB f) * 1,(j1 + 1)) `2 ) }
j1 < width (GoB f)
by A34, NAT_1:13;
then
p in h_strip (GoB f),
j1
by A25, A34, A38, GOBOARD5:6;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A30, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A31, A37, XBOOLE_0:def 4;
verum end; case A39:
(
j1 >= 1 &
j1 + 1
= width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )A40:
j1 < j1 + 1
by NAT_1:13;
A41:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j1) `2 <= r & r <= ((GoB f) * 1,(j1 + 1)) `2 ) }
p in { |[s,r]| where s, r is Real : ((GoB f) * 1,(j1 + 1)) `2 <= r }
;
then
p in h_strip (GoB f),
(j1 + 1)
by A25, A39, GOBOARD5:7;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A30, XBOOLE_0:def 4;
then A42:
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
j1 < width (GoB f)
by A39, NAT_1:13;
then
p in h_strip (GoB f),
j1
by A25, A39, A41, GOBOARD5:6;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A30, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A31, A42, XBOOLE_0:def 4;
verum end; case A43:
(
j1 = 0 &
j1 + 1
< width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )then A44:
(j1 + 1) + 1
<= width (GoB f)
by NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j1 + 1)) `2 <= r & r <= ((GoB f) * 1,((j1 + 1) + 1)) `2 ) }
then
p in h_strip (GoB f),
(j1 + 1)
by A25, A43, GOBOARD5:6;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A30, XBOOLE_0:def 4;
then A45:
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * 1,1) `2 }
by A43;
then
p in h_strip (GoB f),
j1
by A25, A43, GOBOARD5:8;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A30, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A31, A45, XBOOLE_0:def 4;
verum end; case A46:
(
j1 = 0 &
j1 + 1
= width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
p in { |[s,r]| where s, r is Real : ((GoB f) * 1,(j1 + 1)) `2 <= r }
;
then
p in h_strip (GoB f),
(j1 + 1)
by A25, A46, GOBOARD5:7;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A30, XBOOLE_0:def 4;
then A47:
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * 1,1) `2 }
by A46;
then
p in h_strip (GoB f),
j1
by A25, A46, GOBOARD5:8;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A30, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A31, A47, XBOOLE_0:def 4;
verum end; end; end; then
p in Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` ))
by A3, Th3;
then A48:
Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` )) c= Component_of p1
by A3, A4, A8, Th4, GOBRD11:1;
Down (RightComp f),
((L~ f) ` ) is
closed
by Lm4, CONNSP_1:35;
then A49:
Cl (Down (RightComp f),((L~ f) ` )) = Down (RightComp f),
((L~ f) ` )
by PRE_TOPC:52;
Down (LeftComp f),
((L~ f) ` ) is
closed
by Lm3, CONNSP_1:35;
then A50:
Cl (Down (LeftComp f),((L~ f) ` )) = Down (LeftComp f),
((L~ f) ` )
by PRE_TOPC:52;
(Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` )) = Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by GOBRD11:4;
then A51:
Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` )) = (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A50, A49, PRE_TOPC:50;
A52:
(
Down (Int (cell (GoB f),i2,(j1 + 1))),
((L~ f) ` ) c= Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` )) &
Down (Int (cell (GoB f),i2,(j1 + 1))),
((L~ f) ` ) = Int (cell (GoB f),i2,(j1 + 1)) )
by A3, A4, A8, Th4, PRE_TOPC:48;
A53:
(
Down (LeftComp f),
((L~ f) ` ) = LeftComp f &
Down (RightComp f),
((L~ f) ` ) = RightComp f )
by Th6;
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= (LeftComp f) \/ (RightComp f)
by A1, A2, A6, A7, Th4;
then
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by A53, GOBRD11:4;
then A54:
Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` )) c= Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` ))
by PRE_TOPC:49;
p in Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` ))
by A2, A3, A33, Th3;
then
Component_of p1 c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A54, A51, Th6, CONNSP_3:21;
then
Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` )) c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A48, XBOOLE_1:1;
hence
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)
by A53, A52, XBOOLE_1:1;
verum end; case A55:
i2 = len (GoB f)
;
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)reconsider p =
|[((((GoB f) * (len (GoB f)),(j1 + 1)) `1 ) + 1),(((GoB f) * (len (GoB f)),(j1 + 1)) `2 )]| as
Point of
(TOP-REAL 2) ;
A56:
1
< len (GoB f)
by GOBOARD7:34;
reconsider P =
{p} as
Subset of
(TOP-REAL 2) ;
A57:
( ( for
q being
Point of
(TOP-REAL 2) st
q in P holds
((GoB f) * (len (GoB f)),1) `1 < q `1 ) implies
P misses L~ f )
by GOBOARD8:22;
A58:
1
< width (GoB f)
by GOBOARD7:35;
A59:
1
<= 1
+ j1
by NAT_1:11;
then
((GoB f) * (len (GoB f)),(j1 + 1)) `1 = ((GoB f) * (len (GoB f)),1) `1
by A4, A8, A56, GOBOARD5:3;
then A60:
p `1 = (((GoB f) * (len (GoB f)),1) `1 ) + 1
by EUCLID:56;
then A61:
((GoB f) * (len (GoB f)),1) `1 < p `1
by XREAL_1:31;
p in { |[s,r]| where s, r is Real : ((GoB f) * (len (GoB f)),1) `1 <= s }
then A62:
p in v_strip (GoB f),
i2
by A55, A58, GOBOARD5:10;
((GoB f) * (len (GoB f)),1) `1 < (((GoB f) * (len (GoB f)),1) `1 ) + 1
by XREAL_1:31;
then A63:
(
p in {p} &
{p} c= (L~ f) ` )
by A60, A57, SUBSET_1:43, TARSKI:def 1;
then reconsider p1 =
p as
Point of
((TOP-REAL 2) | ((L~ f) ` )) by PRE_TOPC:29;
A64:
(
j1 = 0 or
j1 >= 0 + 1 )
by NAT_1:13;
A65:
now per cases
( ( j1 >= 1 & j1 + 1 < width (GoB f) ) or ( j1 >= 1 & j1 + 1 = width (GoB f) ) or ( j1 = 0 & j1 + 1 < width (GoB f) ) or ( j1 = 0 & j1 + 1 = width (GoB f) ) )
by A4, A8, A64, XXREAL_0:1;
case A66:
(
j1 >= 1 &
j1 + 1
< width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )then A67:
(j1 + 1) + 1
<= width (GoB f)
by NAT_1:13;
A68:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),(j1 + 1)) `2 <= r & r <= ((GoB f) * (len (GoB f)),((j1 + 1) + 1)) `2 ) }
1
<= j1 + 1
by NAT_1:11;
then
p in h_strip (GoB f),
(j1 + 1)
by A56, A66, A68, GOBOARD5:6;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A62, XBOOLE_0:def 4;
then A69:
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
A70:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),j1) `2 <= r & r <= ((GoB f) * (len (GoB f)),(j1 + 1)) `2 ) }
j1 < width (GoB f)
by A66, NAT_1:13;
then
p in h_strip (GoB f),
j1
by A56, A66, A70, GOBOARD5:6;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A62, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A63, A69, XBOOLE_0:def 4;
verum end; case A71:
(
j1 >= 1 &
j1 + 1
= width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )A72:
j1 < j1 + 1
by NAT_1:13;
A73:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),j1) `2 <= r & r <= ((GoB f) * (len (GoB f)),(j1 + 1)) `2 ) }
p in { |[s,r]| where s, r is Real : ((GoB f) * (len (GoB f)),(j1 + 1)) `2 <= r }
;
then
p in h_strip (GoB f),
(j1 + 1)
by A56, A71, GOBOARD5:7;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A62, XBOOLE_0:def 4;
then A74:
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
j1 < width (GoB f)
by A71, NAT_1:13;
then
p in h_strip (GoB f),
j1
by A56, A71, A73, GOBOARD5:6;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A62, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A63, A74, XBOOLE_0:def 4;
verum end; case A75:
(
j1 = 0 &
j1 + 1
< width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )then A76:
(j1 + 1) + 1
<= width (GoB f)
by NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),(j1 + 1)) `2 <= r & r <= ((GoB f) * (len (GoB f)),((j1 + 1) + 1)) `2 ) }
then
p in h_strip (GoB f),
(j1 + 1)
by A56, A75, GOBOARD5:6;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A62, XBOOLE_0:def 4;
then A77:
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * (len (GoB f)),1) `2 }
by A75;
then
p in h_strip (GoB f),
j1
by A56, A75, GOBOARD5:8;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A62, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A63, A77, XBOOLE_0:def 4;
verum end; end; end; then
p in Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` ))
by A3, Th3;
then A78:
Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` )) c= Component_of p1
by A3, A4, A8, Th4, GOBRD11:1;
Down (RightComp f),
((L~ f) ` ) is
closed
by Lm4, CONNSP_1:35;
then A79:
Cl (Down (RightComp f),((L~ f) ` )) = Down (RightComp f),
((L~ f) ` )
by PRE_TOPC:52;
Down (LeftComp f),
((L~ f) ` ) is
closed
by Lm3, CONNSP_1:35;
then A80:
Cl (Down (LeftComp f),((L~ f) ` )) = Down (LeftComp f),
((L~ f) ` )
by PRE_TOPC:52;
(Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` )) = Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by GOBRD11:4;
then A81:
Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` )) = (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A80, A79, PRE_TOPC:50;
A82:
(
Down (Int (cell (GoB f),i2,(j1 + 1))),
((L~ f) ` ) c= Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` )) &
Down (Int (cell (GoB f),i2,(j1 + 1))),
((L~ f) ` ) = Int (cell (GoB f),i2,(j1 + 1)) )
by A3, A4, A8, Th4, PRE_TOPC:48;
A83:
(
Down (LeftComp f),
((L~ f) ` ) = LeftComp f &
Down (RightComp f),
((L~ f) ` ) = RightComp f )
by Th6;
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= (LeftComp f) \/ (RightComp f)
by A1, A2, A6, A7, Th4;
then
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by A83, GOBRD11:4;
then A84:
Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` )) c= Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` ))
by PRE_TOPC:49;
p in Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` ))
by A2, A3, A65, Th3;
then
Component_of p1 c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A84, A81, Th6, CONNSP_3:21;
then
Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` )) c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A78, XBOOLE_1:1;
hence
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)
by A83, A82, XBOOLE_1:1;
verum end; case A85:
(
i2 <> 0 &
i2 <> len (GoB f) & ( for
k being
Element of
NAT holds
( not 1
<= k or not
k + 1
<= len f or not
LSeg (f /. k),
(f /. (k + 1)) = LSeg ((GoB f) * i2,(j1 + 1)),
((GoB f) * (i2 + 1),(j1 + 1)) ) ) )
;
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)then A86:
i2 < len (GoB f)
by A3, XXREAL_0:1;
then A87:
i2 + 1
<= len (GoB f)
by NAT_1:13;
for
k being
Element of
NAT st 1
<= k &
k + 1
<= len f holds
LSeg ((GoB f) * i2,(j1 + 1)),
((GoB f) * (i2 + 1),(j1 + 1)) <> LSeg f,
k
proof
let k be
Element of
NAT ;
( 1 <= k & k + 1 <= len f implies LSeg ((GoB f) * i2,(j1 + 1)),((GoB f) * (i2 + 1),(j1 + 1)) <> LSeg f,k )
assume A88:
( 1
<= k &
k + 1
<= len f )
;
LSeg ((GoB f) * i2,(j1 + 1)),((GoB f) * (i2 + 1),(j1 + 1)) <> LSeg f,k
then
LSeg f,
k = LSeg (f /. k),
(f /. (k + 1))
by TOPREAL1:def 5;
hence
LSeg ((GoB f) * i2,(j1 + 1)),
((GoB f) * (i2 + 1),(j1 + 1)) <> LSeg f,
k
by A85, A88;
verum
end; then A89:
( 1
<= j1 + 1 &
j1 + 1
<= width (GoB f) & 1
<= i2 &
i2 + 1
<= len (GoB f) implies not
(1 / 2) * (((GoB f) * i2,(j1 + 1)) + ((GoB f) * (i2 + 1),(j1 + 1))) in L~ f )
by GOBOARD7:42;
reconsider p =
(1 / 2) * (((GoB f) * i2,(j1 + 1)) + ((GoB f) * (i2 + 1),(j1 + 1))) as
Point of
(TOP-REAL 2) ;
A90:
p `1 =
(1 / 2) * ((((GoB f) * i2,(j1 + 1)) + ((GoB f) * (i2 + 1),(j1 + 1))) `1 )
by TOPREAL3:9
.=
(1 / 2) * ((((GoB f) * i2,(j1 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `1 ))
by TOPREAL3:7
;
reconsider P =
{p} as
Subset of
(TOP-REAL 2) ;
A91:
1
< len (GoB f)
by GOBOARD7:34;
Down (RightComp f),
((L~ f) ` ) is
closed
by Lm4, CONNSP_1:35;
then A92:
Cl (Down (RightComp f),((L~ f) ` )) = Down (RightComp f),
((L~ f) ` )
by PRE_TOPC:52;
Down (LeftComp f),
((L~ f) ` ) is
closed
by Lm3, CONNSP_1:35;
then A93:
Cl (Down (LeftComp f),((L~ f) ` )) = Down (LeftComp f),
((L~ f) ` )
by PRE_TOPC:52;
(Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` )) = Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by GOBRD11:4;
then A94:
Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` )) = (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A93, A92, PRE_TOPC:50;
A95:
(
Down (LeftComp f),
((L~ f) ` ) = LeftComp f &
Down (RightComp f),
((L~ f) ` ) = RightComp f )
by Th6;
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= (LeftComp f) \/ (RightComp f)
by A1, A2, A6, A7, Th4;
then
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by A95, GOBRD11:4;
then A96:
Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` )) c= Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` ))
by PRE_TOPC:49;
A97:
(
Down (Int (cell (GoB f),i2,(j1 + 1))),
((L~ f) ` ) c= Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` )) &
Down (Int (cell (GoB f),i2,(j1 + 1))),
((L~ f) ` ) = Int (cell (GoB f),i2,(j1 + 1)) )
by A3, A4, A8, Th4, PRE_TOPC:48;
A98:
1
<= j1 + 1
by NAT_1:11;
A99:
0 + 1
<= i2
by A85, NAT_1:13;
then A100:
1
< i2 + 1
by NAT_1:13;
( ( for
x being
set st
x in P holds
not
x in L~ f ) implies
P misses L~ f )
by XBOOLE_0:3;
then A101:
(
p in {p} &
{p} c= (L~ f) ` )
by A4, A8, A99, A86, A89, NAT_1:13, SUBSET_1:43, TARSKI:def 1;
then reconsider p1 =
p as
Point of
((TOP-REAL 2) | ((L~ f) ` )) by PRE_TOPC:29;
A102:
1
<= 1
+ j1
by NAT_1:11;
p `2 =
(1 / 2) * ((((GoB f) * i2,(j1 + 1)) + ((GoB f) * (i2 + 1),(j1 + 1))) `2 )
by TOPREAL3:9
.=
(1 / 2) * ((((GoB f) * i2,(j1 + 1)) `2 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `2 ))
by TOPREAL3:7
;
then A103:
p = |[((1 / 2) * ((((GoB f) * i2,(j1 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `1 ))),((1 / 2) * ((((GoB f) * i2,(j1 + 1)) `2 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `2 )))]|
by A90, EUCLID:57;
i2 < i2 + 1
by NAT_1:13;
then A104:
((GoB f) * i2,(j1 + 1)) `1 < ((GoB f) * (i2 + 1),(j1 + 1)) `1
by A4, A8, A99, A87, A102, GOBOARD5:4;
then
(((GoB f) * i2,(j1 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `1 ) < (((GoB f) * (i2 + 1),(j1 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `1 )
by XREAL_1:10;
then A105:
((((GoB f) * i2,(j1 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `1 )) / 2
< ((((GoB f) * (i2 + 1),(j1 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `1 )) / 2
by XREAL_1:76;
(((GoB f) * i2,(j1 + 1)) `1 ) + (((GoB f) * i2,(j1 + 1)) `1 ) < (((GoB f) * i2,(j1 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `1 )
by A104, XREAL_1:10;
then A106:
((((GoB f) * i2,(j1 + 1)) `1 ) + (((GoB f) * i2,(j1 + 1)) `1 )) / 2
< ((((GoB f) * i2,(j1 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j1 + 1)) `1 )) / 2
by XREAL_1:76;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * i2,(j1 + 1)) `1 <= s & s <= ((GoB f) * (i2 + 1),(j1 + 1)) `1 ) }
then A107:
p in v_strip (GoB f),
i2
by A4, A8, A99, A86, A98, GOBOARD5:9;
A108:
(
j1 = 0 or
j1 >= 0 + 1 )
by NAT_1:13;
A109:
now per cases
( ( j1 >= 1 & j1 + 1 < width (GoB f) ) or ( j1 >= 1 & j1 + 1 = width (GoB f) ) or ( j1 = 0 & j1 + 1 < width (GoB f) ) or ( j1 = 0 & j1 + 1 = width (GoB f) ) )
by A4, A8, A108, XXREAL_0:1;
case A110:
(
j1 >= 1 &
j1 + 1
< width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )then A111:
(j1 + 1) + 1
<= width (GoB f)
by NAT_1:13;
A112:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j1 + 1)) `2 <= r & r <= ((GoB f) * 1,((j1 + 1) + 1)) `2 ) }
proof
j1 + 1
< (j1 + 1) + 1
by NAT_1:13;
then A113:
((GoB f) * 1,(j1 + 1)) `2 < ((GoB f) * 1,((j1 + 1) + 1)) `2
by A91, A102, A111, GOBOARD5:5;
(
((GoB f) * i2,(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 &
((GoB f) * (i2 + 1),(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 )
by A3, A4, A8, A99, A87, A102, A100, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j1 + 1)) `2 <= r & r <= ((GoB f) * 1,((j1 + 1) + 1)) `2 ) }
by A103, A113;
verum
end;
1
<= j1 + 1
by NAT_1:11;
then
p in h_strip (GoB f),
(j1 + 1)
by A91, A110, A112, GOBOARD5:6;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A107, XBOOLE_0:def 4;
then A114:
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
A115:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j1) `2 <= r & r <= ((GoB f) * 1,(j1 + 1)) `2 ) }
proof
j1 < j1 + 1
by NAT_1:13;
then A116:
((GoB f) * 1,j1) `2 < ((GoB f) * 1,(j1 + 1)) `2
by A91, A110, GOBOARD5:5;
(
((GoB f) * i2,(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 &
((GoB f) * (i2 + 1),(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 )
by A3, A4, A8, A99, A87, A102, A100, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j1) `2 <= r & r <= ((GoB f) * 1,(j1 + 1)) `2 ) }
by A103, A116;
verum
end;
j1 < width (GoB f)
by A110, NAT_1:13;
then
p in h_strip (GoB f),
j1
by A91, A110, A115, GOBOARD5:6;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A107, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A101, A114, XBOOLE_0:def 4;
verum end; case A117:
(
j1 >= 1 &
j1 + 1
= width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )A118:
j1 < j1 + 1
by NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j1) `2 <= r & r <= ((GoB f) * 1,(j1 + 1)) `2 ) }
proof
A119:
((GoB f) * 1,j1) `2 < ((GoB f) * 1,(j1 + 1)) `2
by A91, A117, A118, GOBOARD5:5;
(
((GoB f) * i2,(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 &
((GoB f) * (i2 + 1),(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 )
by A3, A4, A8, A99, A87, A102, A100, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j1) `2 <= r & r <= ((GoB f) * 1,(j1 + 1)) `2 ) }
by A103, A119;
verum
end; then
p in h_strip (GoB f),
j1
by A91, A117, A118, GOBOARD5:6;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A107, XBOOLE_0:def 4;
then A120:
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : ((GoB f) * 1,(j1 + 1)) `2 <= r }
proof
(
((GoB f) * i2,(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 &
((GoB f) * (i2 + 1),(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 )
by A3, A4, A8, A99, A87, A102, A100, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ((GoB f) * 1,(j1 + 1)) `2 <= r }
by A103;
verum
end; then
p in h_strip (GoB f),
(j1 + 1)
by A91, A117, GOBOARD5:7;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A107, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A101, A120, XBOOLE_0:def 4;
verum end; case A121:
(
j1 = 0 &
j1 + 1
< width (GoB f) )
;
( p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )then A122:
(j1 + 1) + 1
<= width (GoB f)
by NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j1 + 1)) `2 <= r & r <= ((GoB f) * 1,((j1 + 1) + 1)) `2 ) }
proof
j1 + 1
< (j1 + 1) + 1
by NAT_1:13;
then A123:
((GoB f) * 1,(j1 + 1)) `2 < ((GoB f) * 1,((j1 + 1) + 1)) `2
by A91, A102, A122, GOBOARD5:5;
(
((GoB f) * i2,(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 &
((GoB f) * (i2 + 1),(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 )
by A3, A4, A8, A99, A87, A102, A100, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j1 + 1)) `2 <= r & r <= ((GoB f) * 1,((j1 + 1) + 1)) `2 ) }
by A103, A123;
verum
end; then
p in h_strip (GoB f),
(j1 + 1)
by A91, A121, GOBOARD5:6;
then
p in (h_strip (GoB f),(j1 + 1)) /\ (v_strip (GoB f),i2)
by A107, XBOOLE_0:def 4;
then A124:
p in cell (GoB f),
i2,
(j1 + 1)
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * 1,1) `2 }
proof
(
((GoB f) * i2,(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 &
((GoB f) * (i2 + 1),(j1 + 1)) `2 = ((GoB f) * 1,(j1 + 1)) `2 )
by A3, A4, A8, A99, A87, A102, A100, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * 1,1) `2 }
by A103, A121;
verum
end; then
p in h_strip (GoB f),
j1
by A91, A121, GOBOARD5:8;
then
p in (h_strip (GoB f),j1) /\ (v_strip (GoB f),i2)
by A107, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j1
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j1 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j1) /\ ((L~ f) ` ) )
by A101, A124, XBOOLE_0:def 4;
verum end; end; end; then
p in Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` ))
by A3, Th3;
then A125:
Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` )) c= Component_of p1
by A3, A4, A8, Th4, GOBRD11:1;
p in Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` ))
by A2, A3, A109, Th3;
then
Component_of p1 c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A96, A94, Th6, CONNSP_3:21;
then
Cl (Down (Int (cell (GoB f),i2,(j1 + 1))),((L~ f) ` )) c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A125, XBOOLE_1:1;
hence
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)
by A95, A97, XBOOLE_1:1;
verum end; end; end; hence
Int (cell (GoB f),i2,(j1 + 1)) c= (LeftComp f) \/ (RightComp f)
;
verum end; end; end; hence
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)
by A8;
verum end; case A126:
j1 = j2 + 1
;
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)then
j2 < j1
by NAT_1:13;
then A127:
j1 -' 1
< j1
by A126, NAT_D:34;
A128:
j2 < j2 + 1
by NAT_1:13;
A129:
1
<= (j1 -' 1) + 1
by NAT_1:11;
A130:
j2 + 1
< (j2 + 1) + 1
by NAT_1:13;
A131:
( 1
<= j1 &
j1 -' 1
= j1 - 1 )
by A126, NAT_1:11, XREAL_0:def 2;
A132:
1
<= j2 + 1
by NAT_1:11;
A133:
j1 -' 1
= j2
by A126, NAT_D:34;
now per cases
( ex k being Element of NAT st
( 1 <= k & k + 1 <= len f & i2 <> 0 & i2 <> len (GoB f) & LSeg (f /. k),(f /. (k + 1)) = LSeg ((GoB f) * i2,(j2 + 1)),((GoB f) * (i2 + 1),(j2 + 1)) ) or for k being Element of NAT holds
( not 1 <= k or not k + 1 <= len f or not i2 <> 0 or not i2 <> len (GoB f) or not LSeg (f /. k),(f /. (k + 1)) = LSeg ((GoB f) * i2,(j2 + 1)),((GoB f) * (i2 + 1),(j2 + 1)) ) )
;
case
ex
k being
Element of
NAT st
( 1
<= k &
k + 1
<= len f &
i2 <> 0 &
i2 <> len (GoB f) &
LSeg (f /. k),
(f /. (k + 1)) = LSeg ((GoB f) * i2,(j2 + 1)),
((GoB f) * (i2 + 1),(j2 + 1)) )
;
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)then consider k being
Element of
NAT such that A134:
( 1
<= k &
k + 1
<= len f )
and A135:
i2 <> 0
and A136:
i2 <> len (GoB f)
and A137:
LSeg (f /. k),
(f /. (k + 1)) = LSeg ((GoB f) * i2,((j1 -' 1) + 1)),
((GoB f) * (i2 + 1),((j1 -' 1) + 1))
by A133;
now per cases
( ( f /. k = (GoB f) * i2,((j1 -' 1) + 1) & f /. (k + 1) = (GoB f) * (i2 + 1),((j1 -' 1) + 1) ) or ( f /. k = (GoB f) * (i2 + 1),((j1 -' 1) + 1) & f /. (k + 1) = (GoB f) * i2,((j1 -' 1) + 1) ) )
by A137, SPPOL_1:25;
case A138:
(
f /. k = (GoB f) * i2,
((j1 -' 1) + 1) &
f /. (k + 1) = (GoB f) * (i2 + 1),
((j1 -' 1) + 1) )
;
Int (cell (GoB f),i2,(j1 -' 1)) c= (LeftComp f) \/ (RightComp f)A139:
(
Int (right_cell f,k) c= RightComp f &
RightComp f c= (LeftComp f) \/ (RightComp f) )
by A134, GOBOARD9:28, XBOOLE_1:7;
i2 < len (GoB f)
by A3, A136, XXREAL_0:1;
then A140:
i2 + 1
<= len (GoB f)
by NAT_1:13;
j1 -' 1
< width (GoB f)
by A2, A127, XXREAL_0:2;
then
(j1 -' 1) + 1
<= width (GoB f)
by NAT_1:13;
then A141:
(
Indices (GoB f) = [:(dom (GoB f)),(Seg (width (GoB f))):] &
(j1 -' 1) + 1
in Seg (width (GoB f)) )
by A129, FINSEQ_1:3, MATRIX_1:def 5;
1
<= i2 + 1
by NAT_1:11;
then
i2 + 1
in dom (GoB f)
by A140, FINSEQ_3:27;
then A142:
[(i2 + 1),((j1 -' 1) + 1)] in Indices (GoB f)
by A141, ZFMISC_1:106;
i2 >= 0 + 1
by A135, NAT_1:13;
then
i2 in dom (GoB f)
by A3, FINSEQ_3:27;
then
[i2,((j1 -' 1) + 1)] in Indices (GoB f)
by A141, ZFMISC_1:106;
then
right_cell f,
k = cell (GoB f),
i2,
(j1 -' 1)
by A134, A138, A142, GOBOARD5:29;
hence
Int (cell (GoB f),i2,(j1 -' 1)) c= (LeftComp f) \/ (RightComp f)
by A139, XBOOLE_1:1;
verum end; case A143:
(
f /. k = (GoB f) * (i2 + 1),
((j1 -' 1) + 1) &
f /. (k + 1) = (GoB f) * i2,
((j1 -' 1) + 1) )
;
Int (cell (GoB f),i2,(j1 -' 1)) c= (LeftComp f) \/ (RightComp f)A144:
(
Int (left_cell f,k) c= LeftComp f &
LeftComp f c= (LeftComp f) \/ (RightComp f) )
by A134, GOBOARD9:24, XBOOLE_1:7;
i2 < len (GoB f)
by A3, A136, XXREAL_0:1;
then A145:
i2 + 1
<= len (GoB f)
by NAT_1:13;
A146:
(
Indices (GoB f) = [:(dom (GoB f)),(Seg (width (GoB f))):] &
(j1 -' 1) + 1
in Seg (width (GoB f)) )
by A2, A131, FINSEQ_1:3, MATRIX_1:def 5;
1
<= i2 + 1
by NAT_1:11;
then
i2 + 1
in dom (GoB f)
by A145, FINSEQ_3:27;
then A147:
[(i2 + 1),((j1 -' 1) + 1)] in Indices (GoB f)
by A146, ZFMISC_1:106;
i2 >= 0 + 1
by A135, NAT_1:13;
then
i2 in dom (GoB f)
by A3, FINSEQ_3:27;
then
[i2,((j1 -' 1) + 1)] in Indices (GoB f)
by A146, ZFMISC_1:106;
then
left_cell f,
k = cell (GoB f),
i2,
(j1 -' 1)
by A134, A143, A147, GOBOARD5:30;
hence
Int (cell (GoB f),i2,(j1 -' 1)) c= (LeftComp f) \/ (RightComp f)
by A144, XBOOLE_1:1;
verum end; end; end; hence
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)
by A126, NAT_D:34;
verum end; case A148:
for
k being
Element of
NAT holds
( not 1
<= k or not
k + 1
<= len f or not
i2 <> 0 or not
i2 <> len (GoB f) or not
LSeg (f /. k),
(f /. (k + 1)) = LSeg ((GoB f) * i2,(j2 + 1)),
((GoB f) * (i2 + 1),(j2 + 1)) )
;
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)now per cases
( i2 = 0 or i2 = len (GoB f) or ( i2 <> 0 & i2 <> len (GoB f) & ( for k being Element of NAT holds
( not 1 <= k or not k + 1 <= len f or not LSeg (f /. k),(f /. (k + 1)) = LSeg ((GoB f) * i2,(j2 + 1)),((GoB f) * (i2 + 1),(j2 + 1)) ) ) ) )
by A148;
case A149:
i2 = 0
;
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)reconsider p =
|[((((GoB f) * 1,(j2 + 1)) `1 ) - 1),(((GoB f) * 1,(j2 + 1)) `2 )]| as
Point of
(TOP-REAL 2) ;
A150:
1
< len (GoB f)
by GOBOARD7:34;
A151:
1
< width (GoB f)
by GOBOARD7:35;
reconsider P =
{p} as
Subset of
(TOP-REAL 2) ;
A152:
p `1 < (p `1 ) + 1
by XREAL_1:31;
A153:
1
<= j2 + 1
by NAT_1:11;
then
((GoB f) * 1,(j2 + 1)) `1 = ((GoB f) * 1,1) `1
by A2, A126, A150, GOBOARD5:3;
then A154:
p `1 = (((GoB f) * 1,1) `1 ) - 1
by EUCLID:56;
p in { |[s,r]| where s, r is Real : s <= ((GoB f) * 1,1) `1 }
then A155:
p in v_strip (GoB f),
i2
by A149, A151, GOBOARD5:11;
( ( for
q being
Point of
(TOP-REAL 2) st
q in P holds
q `1 < ((GoB f) * 1,1) `1 ) implies
P misses L~ f )
by GOBOARD8:21;
then A156:
(
p in {p} &
{p} c= (L~ f) ` )
by A154, A152, SUBSET_1:43, TARSKI:def 1;
then reconsider p1 =
p as
Point of
((TOP-REAL 2) | ((L~ f) ` )) by PRE_TOPC:29;
A157:
now per cases
( ( j2 + 1 < width (GoB f) & j2 > 0 ) or ( j2 + 1 < width (GoB f) & j2 = 0 ) or ( j2 + 1 = width (GoB f) & j2 > 0 ) or ( j2 + 1 = width (GoB f) & j2 = 0 ) )
by A2, A126, XXREAL_0:1;
case A158:
(
j2 + 1
< width (GoB f) &
j2 > 0 )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )then A159:
(j2 + 1) + 1
<= width (GoB f)
by NAT_1:13;
A160:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j2 + 1)) `2 <= r & r <= ((GoB f) * 1,((j2 + 1) + 1)) `2 ) }
A161:
0 + 1
<= j2
by A158, NAT_1:13;
A162:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j2) `2 <= r & r <= ((GoB f) * 1,(j2 + 1)) `2 ) }
proof
j2 < j2 + 1
by NAT_1:13;
then
((GoB f) * 1,j2) `2 < ((GoB f) * 1,(j2 + 1)) `2
by A2, A126, A150, A161, GOBOARD5:5;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j2) `2 <= r & r <= ((GoB f) * 1,(j2 + 1)) `2 ) }
;
verum
end;
j2 < width (GoB f)
by A158, NAT_1:13;
then
p in h_strip (GoB f),
j2
by A150, A161, A162, GOBOARD5:6;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A155, XBOOLE_0:def 4;
then A163:
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
1
<= j2 + 1
by A161, NAT_1:13;
then
p in h_strip (GoB f),
(j2 + 1)
by A150, A158, A160, GOBOARD5:6;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A155, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A156, A163, XBOOLE_0:def 4;
verum end; case A164:
(
j2 + 1
< width (GoB f) &
j2 = 0 )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )A165:
j2 + 1
< (j2 + 1) + 1
by NAT_1:13;
A166:
(j2 + 1) + 1
<= width (GoB f)
by A164, NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j2 + 1)) `2 <= r & r <= ((GoB f) * 1,((j2 + 1) + 1)) `2 ) }
proof
((GoB f) * 1,(j2 + 1)) `2 < ((GoB f) * 1,((j2 + 1) + 1)) `2
by A132, A150, A166, A165, GOBOARD5:5;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j2 + 1)) `2 <= r & r <= ((GoB f) * 1,((j2 + 1) + 1)) `2 ) }
;
verum
end; then
p in h_strip (GoB f),
(j2 + 1)
by A150, A164, GOBOARD5:6;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A155, XBOOLE_0:def 4;
then A167:
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * 1,(j2 + 1)) `2 }
;
then
p in h_strip (GoB f),
j2
by A150, A164, GOBOARD5:8;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A155, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A156, A167, XBOOLE_0:def 4;
verum end; case A168:
(
j2 + 1
= width (GoB f) &
j2 > 0 )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )then A169:
0 + 1
<= j2
by NAT_1:13;
A170:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j2) `2 <= r & r <= ((GoB f) * 1,(j2 + 1)) `2 ) }
proof
((GoB f) * 1,j2) `2 < ((GoB f) * 1,(j2 + 1)) `2
by A128, A150, A168, A169, GOBOARD5:5;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j2) `2 <= r & r <= ((GoB f) * 1,(j2 + 1)) `2 ) }
;
verum
end;
p in { |[s,r]| where s, r is Real : ((GoB f) * 1,(j2 + 1)) `2 <= r }
;
then
p in h_strip (GoB f),
(j2 + 1)
by A150, A168, GOBOARD5:7;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A155, XBOOLE_0:def 4;
then A171:
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
j2 < width (GoB f)
by A168, NAT_1:13;
then
p in h_strip (GoB f),
j2
by A150, A169, A170, GOBOARD5:6;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A155, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A156, A171, XBOOLE_0:def 4;
verum end; case A172:
(
j2 + 1
= width (GoB f) &
j2 = 0 )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
p in { |[s,r]| where s, r is Real : ((GoB f) * 1,(j2 + 1)) `2 <= r }
;
then
p in h_strip (GoB f),
(j2 + 1)
by A150, A172, GOBOARD5:7;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A155, XBOOLE_0:def 4;
then A173:
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * 1,1) `2 }
by A172;
then
p in h_strip (GoB f),
j2
by A150, A172, GOBOARD5:8;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A155, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A156, A173, XBOOLE_0:def 4;
verum end; end; end; then
p in Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` ))
by A3, A4, Th3;
then A174:
Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` )) c= Component_of p1
by A3, A4, Th4, GOBRD11:1;
Down (RightComp f),
((L~ f) ` ) is
closed
by Lm4, CONNSP_1:35;
then A175:
Cl (Down (RightComp f),((L~ f) ` )) = Down (RightComp f),
((L~ f) ` )
by PRE_TOPC:52;
Down (LeftComp f),
((L~ f) ` ) is
closed
by Lm3, CONNSP_1:35;
then A176:
Cl (Down (LeftComp f),((L~ f) ` )) = Down (LeftComp f),
((L~ f) ` )
by PRE_TOPC:52;
A177:
(
Down (Int (cell (GoB f),i2,j2)),
((L~ f) ` ) c= Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` )) &
Down (Int (cell (GoB f),i2,j2)),
((L~ f) ` ) = Int (cell (GoB f),i2,j2) )
by A3, A4, Th4, PRE_TOPC:48;
(Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` )) = Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by GOBRD11:4;
then A178:
Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` )) = (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A176, A175, PRE_TOPC:50;
A179:
(
Down (LeftComp f),
((L~ f) ` ) = LeftComp f &
Down (RightComp f),
((L~ f) ` ) = RightComp f )
by Th6;
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= (LeftComp f) \/ (RightComp f)
by A1, A2, A6, A7, Th4;
then
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by A179, GOBRD11:4;
then A180:
Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` )) c= Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` ))
by PRE_TOPC:49;
p in Cl (Down (Int (cell (GoB f),i2,(j2 + 1))),((L~ f) ` ))
by A3, A157, Th3;
then
Component_of p1 c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A126, A180, A178, Th6, CONNSP_3:21;
then
Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` )) c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A174, XBOOLE_1:1;
hence
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)
by A179, A177, XBOOLE_1:1;
verum end; case A181:
i2 = len (GoB f)
;
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)reconsider p =
|[((((GoB f) * (len (GoB f)),(j2 + 1)) `1 ) + 1),(((GoB f) * (len (GoB f)),(j2 + 1)) `2 )]| as
Point of
(TOP-REAL 2) ;
A182:
1
< len (GoB f)
by GOBOARD7:34;
reconsider P =
{p} as
Subset of
(TOP-REAL 2) ;
A183:
( ( for
q being
Point of
(TOP-REAL 2) st
q in P holds
((GoB f) * (len (GoB f)),1) `1 < q `1 ) implies
P misses L~ f )
by GOBOARD8:22;
A184:
1
< width (GoB f)
by GOBOARD7:35;
1
<= j2 + 1
by NAT_1:11;
then
((GoB f) * (len (GoB f)),(j2 + 1)) `1 = ((GoB f) * (len (GoB f)),1) `1
by A2, A126, A182, GOBOARD5:3;
then A185:
p `1 = (((GoB f) * (len (GoB f)),1) `1 ) + 1
by EUCLID:56;
then A186:
((GoB f) * (len (GoB f)),1) `1 < p `1
by XREAL_1:31;
p in { |[s,r]| where s, r is Real : ((GoB f) * (len (GoB f)),1) `1 <= s }
then A187:
p in v_strip (GoB f),
i2
by A181, A184, GOBOARD5:10;
((GoB f) * (len (GoB f)),1) `1 < (((GoB f) * (len (GoB f)),1) `1 ) + 1
by XREAL_1:31;
then A188:
(
p in {p} &
{p} c= (L~ f) ` )
by A185, A183, SUBSET_1:43, TARSKI:def 1;
then reconsider p1 =
p as
Point of
((TOP-REAL 2) | ((L~ f) ` )) by PRE_TOPC:29;
A189:
now per cases
( ( j2 + 1 < width (GoB f) & j2 > 0 ) or ( j2 + 1 < width (GoB f) & j2 = 0 ) or ( j2 + 1 = width (GoB f) & j2 > 0 ) or ( j2 + 1 = width (GoB f) & j2 = 0 ) )
by A2, A126, XXREAL_0:1;
case A190:
(
j2 + 1
< width (GoB f) &
j2 > 0 )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )then A191:
(j2 + 1) + 1
<= width (GoB f)
by NAT_1:13;
A192:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),(j2 + 1)) `2 <= r & r <= ((GoB f) * (len (GoB f)),((j2 + 1) + 1)) `2 ) }
1
<= j2 + 1
by NAT_1:11;
then
p in h_strip (GoB f),
(j2 + 1)
by A182, A190, A192, GOBOARD5:6;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A187, XBOOLE_0:def 4;
then A193:
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
A194:
0 + 1
<= j2
by A190, NAT_1:13;
A195:
j2 < j2 + 1
by NAT_1:13;
A196:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),j2) `2 <= r & r <= ((GoB f) * (len (GoB f)),(j2 + 1)) `2 ) }
proof
((GoB f) * (len (GoB f)),j2) `2 < ((GoB f) * (len (GoB f)),(j2 + 1)) `2
by A2, A126, A182, A194, A195, GOBOARD5:5;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),j2) `2 <= r & r <= ((GoB f) * (len (GoB f)),(j2 + 1)) `2 ) }
;
verum
end;
j2 < width (GoB f)
by A190, NAT_1:13;
then
p in h_strip (GoB f),
j2
by A182, A194, A196, GOBOARD5:6;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A187, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A188, A193, XBOOLE_0:def 4;
verum end; case A197:
(
j2 + 1
< width (GoB f) &
j2 = 0 )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )then A198:
(j2 + 1) + 1
<= width (GoB f)
by NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),(j2 + 1)) `2 <= r & r <= ((GoB f) * (len (GoB f)),((j2 + 1) + 1)) `2 ) }
proof
((GoB f) * (len (GoB f)),(j2 + 1)) `2 < ((GoB f) * (len (GoB f)),((j2 + 1) + 1)) `2
by A132, A130, A182, A198, GOBOARD5:5;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),(j2 + 1)) `2 <= r & r <= ((GoB f) * (len (GoB f)),((j2 + 1) + 1)) `2 ) }
;
verum
end; then
p in h_strip (GoB f),
(j2 + 1)
by A182, A197, GOBOARD5:6;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A187, XBOOLE_0:def 4;
then A199:
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * (len (GoB f)),1) `2 }
by A197;
then
p in h_strip (GoB f),
j2
by A182, A197, GOBOARD5:8;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A187, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A188, A199, XBOOLE_0:def 4;
verum end; case A200:
(
j2 + 1
= width (GoB f) &
j2 > 0 )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )then A201:
(
0 + 1
<= j2 &
j2 < width (GoB f) )
by NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * (len (GoB f)),j2) `2 <= r & r <= ((GoB f) * (len (GoB f)),(j2 + 1)) `2 ) }
then
p in h_strip (GoB f),
j2
by A182, A201, GOBOARD5:6;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A187, XBOOLE_0:def 4;
then A202:
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : ((GoB f) * (len (GoB f)),(width (GoB f))) `2 <= r }
by A200;
then
p in h_strip (GoB f),
(j2 + 1)
by A182, A200, GOBOARD5:7;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A187, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A188, A202, XBOOLE_0:def 4;
verum end; end; end; then
p in Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` ))
by A3, A4, Th3;
then A203:
Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` )) c= Component_of p1
by A3, A4, Th4, GOBRD11:1;
Down (RightComp f),
((L~ f) ` ) is
closed
by Lm4, CONNSP_1:35;
then A204:
Cl (Down (RightComp f),((L~ f) ` )) = Down (RightComp f),
((L~ f) ` )
by PRE_TOPC:52;
Down (LeftComp f),
((L~ f) ` ) is
closed
by Lm3, CONNSP_1:35;
then A205:
Cl (Down (LeftComp f),((L~ f) ` )) = Down (LeftComp f),
((L~ f) ` )
by PRE_TOPC:52;
A206:
(
Down (Int (cell (GoB f),i2,j2)),
((L~ f) ` ) c= Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` )) &
Down (Int (cell (GoB f),i2,j2)),
((L~ f) ` ) = Int (cell (GoB f),i2,j2) )
by A3, A4, Th4, PRE_TOPC:48;
(Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` )) = Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by GOBRD11:4;
then A207:
Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` )) = (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A205, A204, PRE_TOPC:50;
A208:
(
Down (LeftComp f),
((L~ f) ` ) = LeftComp f &
Down (RightComp f),
((L~ f) ` ) = RightComp f )
by Th6;
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= (LeftComp f) \/ (RightComp f)
by A1, A2, A6, A7, Th4;
then
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by A208, GOBRD11:4;
then A209:
Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` )) c= Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` ))
by PRE_TOPC:49;
p in Cl (Down (Int (cell (GoB f),i2,(j2 + 1))),((L~ f) ` ))
by A3, A189, Th3;
then
Component_of p1 c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A126, A209, A207, Th6, CONNSP_3:21;
then
Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` )) c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A203, XBOOLE_1:1;
hence
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)
by A208, A206, XBOOLE_1:1;
verum end; case A210:
(
i2 <> 0 &
i2 <> len (GoB f) & ( for
k being
Element of
NAT holds
( not 1
<= k or not
k + 1
<= len f or not
LSeg (f /. k),
(f /. (k + 1)) = LSeg ((GoB f) * i2,(j2 + 1)),
((GoB f) * (i2 + 1),(j2 + 1)) ) ) )
;
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)then A211:
i2 < len (GoB f)
by A3, XXREAL_0:1;
then A212:
i2 + 1
<= len (GoB f)
by NAT_1:13;
for
k being
Element of
NAT st 1
<= k &
k + 1
<= len f holds
LSeg ((GoB f) * i2,(j2 + 1)),
((GoB f) * (i2 + 1),(j2 + 1)) <> LSeg f,
k
proof
let k be
Element of
NAT ;
( 1 <= k & k + 1 <= len f implies LSeg ((GoB f) * i2,(j2 + 1)),((GoB f) * (i2 + 1),(j2 + 1)) <> LSeg f,k )
assume A213:
( 1
<= k &
k + 1
<= len f )
;
LSeg ((GoB f) * i2,(j2 + 1)),((GoB f) * (i2 + 1),(j2 + 1)) <> LSeg f,k
then
LSeg f,
k = LSeg (f /. k),
(f /. (k + 1))
by TOPREAL1:def 5;
hence
LSeg ((GoB f) * i2,(j2 + 1)),
((GoB f) * (i2 + 1),(j2 + 1)) <> LSeg f,
k
by A210, A213;
verum
end; then A214:
( 1
<= j2 + 1 &
j2 + 1
<= width (GoB f) & 1
<= i2 &
i2 + 1
<= len (GoB f) implies not
(1 / 2) * (((GoB f) * i2,(j2 + 1)) + ((GoB f) * (i2 + 1),(j2 + 1))) in L~ f )
by GOBOARD7:42;
reconsider p =
(1 / 2) * (((GoB f) * i2,(j2 + 1)) + ((GoB f) * (i2 + 1),(j2 + 1))) as
Point of
(TOP-REAL 2) ;
A215:
p `1 =
(1 / 2) * ((((GoB f) * i2,(j2 + 1)) + ((GoB f) * (i2 + 1),(j2 + 1))) `1 )
by TOPREAL3:9
.=
(1 / 2) * ((((GoB f) * i2,(j2 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `1 ))
by TOPREAL3:7
;
reconsider P =
{p} as
Subset of
(TOP-REAL 2) ;
A216:
1
< len (GoB f)
by GOBOARD7:34;
Down (RightComp f),
((L~ f) ` ) is
closed
by Lm4, CONNSP_1:35;
then A217:
Cl (Down (RightComp f),((L~ f) ` )) = Down (RightComp f),
((L~ f) ` )
by PRE_TOPC:52;
Down (LeftComp f),
((L~ f) ` ) is
closed
by Lm3, CONNSP_1:35;
then A218:
Cl (Down (LeftComp f),((L~ f) ` )) = Down (LeftComp f),
((L~ f) ` )
by PRE_TOPC:52;
(Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` )) = Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by GOBRD11:4;
then A219:
Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` )) = (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A218, A217, PRE_TOPC:50;
A220:
1
<= j2 + 1
by NAT_1:11;
A221:
(
Down (Int (cell (GoB f),i2,j2)),
((L~ f) ` ) c= Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` )) &
Down (Int (cell (GoB f),i2,j2)),
((L~ f) ` ) = Int (cell (GoB f),i2,j2) )
by A3, A4, Th4, PRE_TOPC:48;
A222:
(
Down (LeftComp f),
((L~ f) ` ) = LeftComp f &
Down (RightComp f),
((L~ f) ` ) = RightComp f )
by Th6;
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= (LeftComp f) \/ (RightComp f)
by A1, A2, A6, A7, Th4;
then
Down (Int (cell (GoB f),i2,j1)),
((L~ f) ` ) c= Down ((LeftComp f) \/ (RightComp f)),
((L~ f) ` )
by A222, GOBRD11:4;
then A223:
Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` )) c= Cl (Down ((LeftComp f) \/ (RightComp f)),((L~ f) ` ))
by PRE_TOPC:49;
A224:
0 + 1
<= i2
by A210, NAT_1:13;
then A225:
1
< i2 + 1
by NAT_1:13;
( ( for
x being
set st
x in P holds
not
x in L~ f ) implies
P misses L~ f )
by XBOOLE_0:3;
then A226:
(
p in {p} &
{p} c= (L~ f) ` )
by A2, A126, A224, A211, A214, NAT_1:13, SUBSET_1:43, TARSKI:def 1;
then reconsider p1 =
p as
Point of
((TOP-REAL 2) | ((L~ f) ` )) by PRE_TOPC:29;
A227:
1
<= 1
+ j2
by NAT_1:11;
i2 < i2 + 1
by NAT_1:13;
then A228:
((GoB f) * i2,(j2 + 1)) `1 < ((GoB f) * (i2 + 1),(j2 + 1)) `1
by A2, A126, A224, A212, A220, GOBOARD5:4;
then
(((GoB f) * i2,(j2 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `1 ) < (((GoB f) * (i2 + 1),(j2 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `1 )
by XREAL_1:10;
then A229:
((((GoB f) * i2,(j2 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `1 )) / 2
< ((((GoB f) * (i2 + 1),(j2 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `1 )) / 2
by XREAL_1:76;
(((GoB f) * i2,(j2 + 1)) `1 ) + (((GoB f) * i2,(j2 + 1)) `1 ) < (((GoB f) * i2,(j2 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `1 )
by A228, XREAL_1:10;
then A230:
((((GoB f) * i2,(j2 + 1)) `1 ) + (((GoB f) * i2,(j2 + 1)) `1 )) / 2
< ((((GoB f) * i2,(j2 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `1 )) / 2
by XREAL_1:76;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * i2,(j2 + 1)) `1 <= s & s <= ((GoB f) * (i2 + 1),(j2 + 1)) `1 ) }
then A231:
p in v_strip (GoB f),
i2
by A2, A126, A224, A211, A227, GOBOARD5:9;
p `2 =
(1 / 2) * ((((GoB f) * i2,(j2 + 1)) + ((GoB f) * (i2 + 1),(j2 + 1))) `2 )
by TOPREAL3:9
.=
(1 / 2) * ((((GoB f) * i2,(j2 + 1)) `2 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `2 ))
by TOPREAL3:7
;
then A232:
p = |[((1 / 2) * ((((GoB f) * i2,(j2 + 1)) `1 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `1 ))),((1 / 2) * ((((GoB f) * i2,(j2 + 1)) `2 ) + (((GoB f) * (i2 + 1),(j2 + 1)) `2 )))]|
by A215, EUCLID:57;
A233:
(
j2 = 0 or
j2 >= 0 + 1 )
by NAT_1:13;
A234:
now per cases
( ( j2 >= 1 & j2 + 1 < width (GoB f) ) or ( j2 >= 1 & j2 + 1 = width (GoB f) ) or ( j2 = 0 & j2 + 1 < width (GoB f) ) or ( j2 = 0 & j2 + 1 = width (GoB f) ) )
by A2, A126, A233, XXREAL_0:1;
case A235:
(
j2 >= 1 &
j2 + 1
< width (GoB f) )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )then A236:
(j2 + 1) + 1
<= width (GoB f)
by NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j2 + 1)) `2 <= r & r <= ((GoB f) * 1,((j2 + 1) + 1)) `2 ) }
proof
j2 + 1
< (j2 + 1) + 1
by NAT_1:13;
then A237:
((GoB f) * 1,(j2 + 1)) `2 < ((GoB f) * 1,((j2 + 1) + 1)) `2
by A216, A220, A236, GOBOARD5:5;
(
((GoB f) * i2,(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 &
((GoB f) * (i2 + 1),(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 )
by A2, A3, A126, A224, A212, A220, A225, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j2 + 1)) `2 <= r & r <= ((GoB f) * 1,((j2 + 1) + 1)) `2 ) }
by A232, A237;
verum
end; then
p in h_strip (GoB f),
(j2 + 1)
by A216, A227, A235, GOBOARD5:6;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A231, XBOOLE_0:def 4;
then A238:
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
A239:
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j2) `2 <= r & r <= ((GoB f) * 1,(j2 + 1)) `2 ) }
proof
j2 < j2 + 1
by NAT_1:13;
then A240:
((GoB f) * 1,j2) `2 < ((GoB f) * 1,(j2 + 1)) `2
by A216, A235, GOBOARD5:5;
(
((GoB f) * i2,(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 &
((GoB f) * (i2 + 1),(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 )
by A2, A3, A126, A224, A212, A220, A225, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j2) `2 <= r & r <= ((GoB f) * 1,(j2 + 1)) `2 ) }
by A232, A240;
verum
end;
j2 < width (GoB f)
by A235, NAT_1:13;
then
p in h_strip (GoB f),
j2
by A216, A235, A239, GOBOARD5:6;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A231, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A226, A238, XBOOLE_0:def 4;
verum end; case A241:
(
j2 >= 1 &
j2 + 1
= width (GoB f) )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )A242:
j2 < j2 + 1
by NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j2) `2 <= r & r <= ((GoB f) * 1,(j2 + 1)) `2 ) }
proof
A243:
((GoB f) * 1,j2) `2 < ((GoB f) * 1,(j2 + 1)) `2
by A216, A241, A242, GOBOARD5:5;
(
((GoB f) * i2,(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 &
((GoB f) * (i2 + 1),(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 )
by A2, A3, A126, A224, A212, A220, A225, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,j2) `2 <= r & r <= ((GoB f) * 1,(j2 + 1)) `2 ) }
by A232, A243;
verum
end; then
p in h_strip (GoB f),
j2
by A216, A241, A242, GOBOARD5:6;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A231, XBOOLE_0:def 4;
then A244:
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : ((GoB f) * 1,(j2 + 1)) `2 <= r }
proof
(
((GoB f) * i2,(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 &
((GoB f) * (i2 + 1),(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 )
by A2, A3, A126, A224, A212, A220, A225, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ((GoB f) * 1,(j2 + 1)) `2 <= r }
by A232;
verum
end; then
p in h_strip (GoB f),
(j2 + 1)
by A216, A241, GOBOARD5:7;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A231, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A226, A244, XBOOLE_0:def 4;
verum end; case A245:
(
j2 = 0 &
j2 + 1
< width (GoB f) )
;
( p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) & p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )then A246:
(j2 + 1) + 1
<= width (GoB f)
by NAT_1:13;
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j2 + 1)) `2 <= r & r <= ((GoB f) * 1,((j2 + 1) + 1)) `2 ) }
proof
j2 + 1
< (j2 + 1) + 1
by NAT_1:13;
then A247:
((GoB f) * 1,(j2 + 1)) `2 < ((GoB f) * 1,((j2 + 1) + 1)) `2
by A216, A220, A246, GOBOARD5:5;
(
((GoB f) * i2,(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 &
((GoB f) * (i2 + 1),(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 )
by A2, A3, A126, A224, A212, A220, A225, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : ( ((GoB f) * 1,(j2 + 1)) `2 <= r & r <= ((GoB f) * 1,((j2 + 1) + 1)) `2 ) }
by A232, A247;
verum
end; then
p in h_strip (GoB f),
j1
by A126, A216, A245, GOBOARD5:6;
then
p in (h_strip (GoB f),(j2 + 1)) /\ (v_strip (GoB f),i2)
by A126, A231, XBOOLE_0:def 4;
then A248:
p in cell (GoB f),
i2,
(j2 + 1)
by GOBOARD5:def 3;
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * 1,1) `2 }
proof
(
((GoB f) * i2,(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 &
((GoB f) * (i2 + 1),(j2 + 1)) `2 = ((GoB f) * 1,(j2 + 1)) `2 )
by A2, A3, A126, A224, A212, A220, A225, GOBOARD5:2;
hence
p in { |[s,r]| where s, r is Real : r <= ((GoB f) * 1,1) `2 }
by A232, A245;
verum
end; then
p in h_strip (GoB f),
j2
by A216, A245, GOBOARD5:8;
then
p in (h_strip (GoB f),j2) /\ (v_strip (GoB f),i2)
by A231, XBOOLE_0:def 4;
then
p in cell (GoB f),
i2,
j2
by GOBOARD5:def 3;
hence
(
p in (cell (GoB f),i2,(j2 + 1)) /\ ((L~ f) ` ) &
p in (cell (GoB f),i2,j2) /\ ((L~ f) ` ) )
by A226, A248, XBOOLE_0:def 4;
verum end; end; end; then
p in Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` ))
by A3, A4, Th3;
then A249:
Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` )) c= Component_of p1
by A3, A4, Th4, GOBRD11:1;
p in Cl (Down (Int (cell (GoB f),i2,j1)),((L~ f) ` ))
by A3, A126, A234, Th3;
then
Component_of p1 c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A223, A219, Th6, CONNSP_3:21;
then
Cl (Down (Int (cell (GoB f),i2,j2)),((L~ f) ` )) c= (Down (LeftComp f),((L~ f) ` )) \/ (Down (RightComp f),((L~ f) ` ))
by A249, XBOOLE_1:1;
hence
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)
by A222, A221, XBOOLE_1:1;
verum end; end; end; hence
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)
;
verum end; end; end; hence
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)
;
verum end; end; end; hence
Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f)
;
verum end;
hence
( not Int (cell (GoB f),i1,j1) c= (LeftComp f) \/ (RightComp f) or Int (cell (GoB f),i2,j2) c= (LeftComp f) \/ (RightComp f) )
; verum