let i1 be Element of NAT ; :: thesis: for p being Point of (TOP-REAL 2)
for Y being non empty finite Subset of NAT
for h being non constant standard special_circular_sequence st p `1 = W-bound (L~ h) & p in L~ h & Y = { j where j is Element of NAT : ( [1,j] in Indices (GoB h) & ex i being Element of NAT st
( i in dom h & h /. i = (GoB h) * 1,j ) ) } & i1 = min Y holds
((GoB h) * 1,i1) `2 <= p `2
let p be Point of (TOP-REAL 2); :: thesis: for Y being non empty finite Subset of NAT
for h being non constant standard special_circular_sequence st p `1 = W-bound (L~ h) & p in L~ h & Y = { j where j is Element of NAT : ( [1,j] in Indices (GoB h) & ex i being Element of NAT st
( i in dom h & h /. i = (GoB h) * 1,j ) ) } & i1 = min Y holds
((GoB h) * 1,i1) `2 <= p `2
let Y be non empty finite Subset of NAT ; :: thesis: for h being non constant standard special_circular_sequence st p `1 = W-bound (L~ h) & p in L~ h & Y = { j where j is Element of NAT : ( [1,j] in Indices (GoB h) & ex i being Element of NAT st
( i in dom h & h /. i = (GoB h) * 1,j ) ) } & i1 = min Y holds
((GoB h) * 1,i1) `2 <= p `2
let h be non constant standard special_circular_sequence; :: thesis: ( p `1 = W-bound (L~ h) & p in L~ h & Y = { j where j is Element of NAT : ( [1,j] in Indices (GoB h) & ex i being Element of NAT st
( i in dom h & h /. i = (GoB h) * 1,j ) ) } & i1 = min Y implies ((GoB h) * 1,i1) `2 <= p `2 )
assume A1:
( p `1 = W-bound (L~ h) & p in L~ h & Y = { j where j is Element of NAT : ( [1,j] in Indices (GoB h) & ex i being Element of NAT st
( i in dom h & h /. i = (GoB h) * 1,j ) ) } & i1 = min Y )
; :: thesis: ((GoB h) * 1,i1) `2 <= p `2
then A2:
p `1 = ((GoB h) * 1,1) `1
by Th39;
A3:
1 <= width (GoB h)
by GOBOARD7:35;
A4:
1 <= len (GoB h)
by GOBOARD7:34;
consider i being Element of NAT such that
A5:
( 1 <= i & i + 1 <= len h & p in LSeg (h /. i),(h /. (i + 1)) )
by A1, SPPOL_2:14;
i <= i + 1
by NAT_1:11;
then A6:
i <= len h
by A5, XXREAL_0:2;
A7:
1 <= i + 1
by A5, XREAL_1:147;
now per cases
( LSeg h,i is vertical or LSeg h,i is horizontal )
by SPPOL_1:41;
case
LSeg h,
i is
vertical
;
:: thesis: ((GoB h) * 1,i1) `2 <= p `2 then
LSeg (h /. i),
(h /. (i + 1)) is
vertical
by A5, TOPREAL1:def 5;
then
(h /. i) `1 = (h /. (i + 1)) `1
by SPPOL_1:37;
then A8:
(
p `1 = (h /. (i + 1)) `1 &
p `1 = (h /. i) `1 )
by A5, GOBOARD7:5;
now per cases
( (h /. i) `2 <= (h /. (i + 1)) `2 or (h /. i) `2 > (h /. (i + 1)) `2 )
;
case
(h /. i) `2 <= (h /. (i + 1)) `2
;
:: thesis: ((GoB h) * 1,i1) `2 <= p `2 then A9:
(
(h /. i) `2 <= p `2 &
p `2 <= (h /. (i + 1)) `2 )
by A5, TOPREAL1:10;
((GoB h) * 1,i1) `2 <= (h /. i) `2
by A1, A2, A4, A5, A6, A8, Th43;
hence
((GoB h) * 1,i1) `2 <= p `2
by A9, XXREAL_0:2;
:: thesis: verum end; case
(h /. i) `2 > (h /. (i + 1)) `2
;
:: thesis: ((GoB h) * 1,i1) `2 <= p `2 then A10:
(
(h /. (i + 1)) `2 <= p `2 &
p `2 <= (h /. i) `2 )
by A5, TOPREAL1:10;
((GoB h) * 1,i1) `2 <= (h /. (i + 1)) `2
by A1, A2, A4, A5, A7, A8, Th43;
hence
((GoB h) * 1,i1) `2 <= p `2
by A10, XXREAL_0:2;
:: thesis: verum end; end; end; hence
((GoB h) * 1,i1) `2 <= p `2
;
:: thesis: verum end; case
LSeg h,
i is
horizontal
;
:: thesis: ((GoB h) * 1,i1) `2 <= p `2 then
LSeg (h /. i),
(h /. (i + 1)) is
horizontal
by A5, TOPREAL1:def 5;
then
(h /. i) `2 = (h /. (i + 1)) `2
by SPPOL_1:36;
then A11:
(
p `2 = (h /. (i + 1)) `2 &
p `2 = (h /. i) `2 )
by A5, GOBOARD7:6;
now per cases
( (h /. i) `1 <= (h /. (i + 1)) `1 or (h /. i) `1 > (h /. (i + 1)) `1 )
;
case
(h /. i) `1 <= (h /. (i + 1)) `1
;
:: thesis: ((GoB h) * 1,i1) `2 <= p `2 then A12:
(h /. i) `1 <= ((GoB h) * 1,1) `1
by A2, A5, TOPREAL1:9;
(h /. i) `1 >= ((GoB h) * 1,1) `1
by A3, A5, A6, Th7;
then
(h /. i) `1 = ((GoB h) * 1,1) `1
by A12, XXREAL_0:1;
hence
((GoB h) * 1,i1) `2 <= p `2
by A1, A4, A5, A6, A11, Th43;
:: thesis: verum end; case
(h /. i) `1 > (h /. (i + 1)) `1
;
:: thesis: ((GoB h) * 1,i1) `2 <= p `2 then A13:
(h /. (i + 1)) `1 <= ((GoB h) * 1,1) `1
by A2, A5, TOPREAL1:9;
(h /. (i + 1)) `1 >= ((GoB h) * 1,1) `1
by A3, A5, A7, Th7;
then
(h /. (i + 1)) `1 = ((GoB h) * 1,1) `1
by A13, XXREAL_0:1;
hence
((GoB h) * 1,i1) `2 <= p `2
by A1, A4, A5, A7, A11, Th43;
:: thesis: verum end; end; end; hence
((GoB h) * 1,i1) `2 <= p `2
;
:: thesis: verum end; end; end;
hence
((GoB h) * 1,i1) `2 <= p `2
; :: thesis: verum