let G be Go-board; :: thesis: for f being non constant standard special_circular_sequence st f is_sequence_on G holds
for k being Element of NAT st 1 <= k & k + 1 <= len f holds
( (right_cell f,k,G) \ (L~ f) c= RightComp f & (left_cell f,k,G) \ (L~ f) c= LeftComp f )
let f be non constant standard special_circular_sequence; :: thesis: ( f is_sequence_on G implies for k being Element of NAT st 1 <= k & k + 1 <= len f holds
( (right_cell f,k,G) \ (L~ f) c= RightComp f & (left_cell f,k,G) \ (L~ f) c= LeftComp f ) )
assume A1:
f is_sequence_on G
; :: thesis: for k being Element of NAT st 1 <= k & k + 1 <= len f holds
( (right_cell f,k,G) \ (L~ f) c= RightComp f & (left_cell f,k,G) \ (L~ f) c= LeftComp f )
let k be Element of NAT ; :: thesis: ( 1 <= k & k + 1 <= len f implies ( (right_cell f,k,G) \ (L~ f) c= RightComp f & (left_cell f,k,G) \ (L~ f) c= LeftComp f ) )
assume A2:
( 1 <= k & k + 1 <= len f )
; :: thesis: ( (right_cell f,k,G) \ (L~ f) c= RightComp f & (left_cell f,k,G) \ (L~ f) c= LeftComp f )
set rc = (right_cell f,k,G) \ (L~ f);
A3:
(right_cell f,k,G) \ (L~ f) = (right_cell f,k,G) /\ ((L~ f) ` )
by SUBSET_1:32;
A4:
(right_cell f,k,G) \ (L~ f) c= right_cell f,k,G
by XBOOLE_1:36;
right_cell f,k,G c= right_cell f,k
by A1, A2, GOBRD13:34;
then
(right_cell f,k,G) \ (L~ f) c= right_cell f,k
by A4, XBOOLE_1:1;
then A5:
Int ((right_cell f,k,G) \ (L~ f)) c= Int (right_cell f,k)
by TOPS_1:48;
Int (right_cell f,k) c= RightComp f
by A2, GOBOARD9:28;
then A6:
Int ((right_cell f,k,G) \ (L~ f)) c= RightComp f
by A5, XBOOLE_1:1;
A7:
Int (right_cell f,k,G) <> {}
by A1, A2, Th11;
A8:
Int (right_cell f,k,G) misses L~ f
by A1, A2, Th17;
A9:
Int (right_cell f,k,G) c= right_cell f,k,G
by TOPS_1:44;
((right_cell f,k,G) \ (L~ f)) \/ (L~ f) = (right_cell f,k,G) \/ (L~ f)
by XBOOLE_1:39;
then
right_cell f,k,G c= ((right_cell f,k,G) \ (L~ f)) \/ (L~ f)
by XBOOLE_1:7;
then A10:
Int (right_cell f,k,G) c= ((right_cell f,k,G) \ (L~ f)) \/ (L~ f)
by A9, XBOOLE_1:1;
then A11:
Int (right_cell f,k,G) c= (right_cell f,k,G) \ (L~ f)
by A8, XBOOLE_1:73;
Int (Int (right_cell f,k,G)) c= Int ((right_cell f,k,G) \ (L~ f))
by A8, A10, TOPS_1:48, XBOOLE_1:73;
then A12:
(right_cell f,k,G) \ (L~ f) meets Int ((right_cell f,k,G) \ (L~ f))
by A7, A11, XBOOLE_1:68;
A13:
(right_cell f,k,G) \ (L~ f) is connected
by A1, A2, Th28;
A14:
RightComp f is_a_component_of (L~ f) `
by GOBOARD9:def 2;
(right_cell f,k,G) \ (L~ f) c= (L~ f) `
by A3, XBOOLE_1:17;
hence
(right_cell f,k,G) \ (L~ f) c= RightComp f
by A6, A12, A13, A14, GOBOARD9:6; :: thesis: (left_cell f,k,G) \ (L~ f) c= LeftComp f
set lc = (left_cell f,k,G) \ (L~ f);
A15:
(left_cell f,k,G) \ (L~ f) = (left_cell f,k,G) /\ ((L~ f) ` )
by SUBSET_1:32;
A16:
(left_cell f,k,G) \ (L~ f) c= left_cell f,k,G
by XBOOLE_1:36;
left_cell f,k,G c= left_cell f,k
by A1, A2, GOBRD13:34;
then
(left_cell f,k,G) \ (L~ f) c= left_cell f,k
by A16, XBOOLE_1:1;
then A17:
Int ((left_cell f,k,G) \ (L~ f)) c= Int (left_cell f,k)
by TOPS_1:48;
Int (left_cell f,k) c= LeftComp f
by A2, GOBOARD9:24;
then A18:
Int ((left_cell f,k,G) \ (L~ f)) c= LeftComp f
by A17, XBOOLE_1:1;
A19:
Int (left_cell f,k,G) <> {}
by A1, A2, Th11;
A20:
Int (left_cell f,k,G) misses L~ f
by A1, A2, Th17;
A21:
Int (left_cell f,k,G) c= left_cell f,k,G
by TOPS_1:44;
((left_cell f,k,G) \ (L~ f)) \/ (L~ f) = (left_cell f,k,G) \/ (L~ f)
by XBOOLE_1:39;
then
left_cell f,k,G c= ((left_cell f,k,G) \ (L~ f)) \/ (L~ f)
by XBOOLE_1:7;
then A22:
Int (left_cell f,k,G) c= ((left_cell f,k,G) \ (L~ f)) \/ (L~ f)
by A21, XBOOLE_1:1;
then A23:
Int (left_cell f,k,G) c= (left_cell f,k,G) \ (L~ f)
by A20, XBOOLE_1:73;
Int (Int (left_cell f,k,G)) c= Int ((left_cell f,k,G) \ (L~ f))
by A20, A22, TOPS_1:48, XBOOLE_1:73;
then A24:
(left_cell f,k,G) \ (L~ f) meets Int ((left_cell f,k,G) \ (L~ f))
by A19, A23, XBOOLE_1:68;
A25:
(left_cell f,k,G) \ (L~ f) is connected
by A1, A2, Th28;
A26:
LeftComp f is_a_component_of (L~ f) `
by GOBOARD9:def 1;
(left_cell f,k,G) \ (L~ f) c= (L~ f) `
by A15, XBOOLE_1:17;
hence
(left_cell f,k,G) \ (L~ f) c= LeftComp f
by A18, A24, A25, A26, GOBOARD9:6; :: thesis: verum