let C be non empty compact non horizontal non vertical Subset of (TOP-REAL 2); :: thesis: for n being Nat ex i being Element of NAT st
( 1 <= i & i + 1 <= len (Gauge C,n) & N-min C in cell (Gauge C,n),i,((width (Gauge C,n)) -' 1) & N-min C <> (Gauge C,n) * i,((width (Gauge C,n)) -' 1) )
let n be Nat; :: thesis: ex i being Element of NAT st
( 1 <= i & i + 1 <= len (Gauge C,n) & N-min C in cell (Gauge C,n),i,((width (Gauge C,n)) -' 1) & N-min C <> (Gauge C,n) * i,((width (Gauge C,n)) -' 1) )
A1:
n in NAT
by ORDINAL1:def 13;
set G = Gauge C,n;
A2:
len (Gauge C,n) = width (Gauge C,n)
by JORDAN8:def 1;
defpred S1[ Nat] means ( 1 <= $1 & $1 < len (Gauge C,n) & ((Gauge C,n) * $1,((width (Gauge C,n)) -' 1)) `1 < (N-min C) `1 );
A3:
for k being Nat st S1[k] holds
k <= len (Gauge C,n)
;
A4:
( len (Gauge C,n) = (2 |^ n) + 3 & len (Gauge C,n) = width (Gauge C,n) )
by JORDAN8:def 1;
A5:
len (Gauge C,n) >= 4
by JORDAN8:13;
then A6:
1 < len (Gauge C,n)
by XXREAL_0:2;
then A7:
1 <= (len (Gauge C,n)) -' 1
by NAT_D:49;
A8:
(len (Gauge C,n)) -' 1 <= len (Gauge C,n)
by NAT_D:35;
(NW-corner C) `1 <= (N-min C) `1
by PSCOMP_1:97;
then A9:
W-bound C <= (N-min C) `1
by EUCLID:56;
A10:
2 <= len (Gauge C,n)
by A5, XXREAL_0:2;
((Gauge C,n) * 2,((width (Gauge C,n)) -' 1)) `1 = W-bound C
by A1, A2, A7, JORDAN8:14, NAT_D:35;
then
((Gauge C,n) * 1,((width (Gauge C,n)) -' 1)) `1 < W-bound C
by A4, A7, A8, A10, GOBOARD5:4;
then
((Gauge C,n) * 1,((width (Gauge C,n)) -' 1)) `1 < (N-min C) `1
by A9, XXREAL_0:2;
then A11:
ex k being Nat st S1[k]
by A6;
ex i being Nat st
( S1[i] & ( for n being Nat st S1[n] holds
n <= i ) )
from NAT_1:sch 6(A3, A11);
then consider i being Nat such that
A12:
( 1 <= i & i < len (Gauge C,n) )
and
A13:
((Gauge C,n) * i,((width (Gauge C,n)) -' 1)) `1 < (N-min C) `1
and
A14:
for n being Nat st S1[n] holds
n <= i
;
reconsider i = i as Element of NAT by ORDINAL1:def 13;
take
i
; :: thesis: ( 1 <= i & i + 1 <= len (Gauge C,n) & N-min C in cell (Gauge C,n),i,((width (Gauge C,n)) -' 1) & N-min C <> (Gauge C,n) * i,((width (Gauge C,n)) -' 1) )
thus
( 1 <= i & i + 1 <= len (Gauge C,n) )
by A12, NAT_1:13; :: thesis: ( N-min C in cell (Gauge C,n),i,((width (Gauge C,n)) -' 1) & N-min C <> (Gauge C,n) * i,((width (Gauge C,n)) -' 1) )
A15:
LSeg ((Gauge C,n) * i,((width (Gauge C,n)) -' 1)),((Gauge C,n) * (i + 1),((width (Gauge C,n)) -' 1)) c= cell (Gauge C,n),i,((width (Gauge C,n)) -' 1)
by A4, A7, A12, GOBOARD5:23, NAT_D:35;
A16:
i + 1 <= len (Gauge C,n)
by A12, NAT_1:13;
A17:
1 <= i + 1
by NAT_1:12;
(N-min C) `2 = N-bound C
by EUCLID:56;
then A18:
( ((Gauge C,n) * i,((width (Gauge C,n)) -' 1)) `2 = (N-min C) `2 & (N-min C) `2 = ((Gauge C,n) * (i + 1),((width (Gauge C,n)) -' 1)) `2 )
by A1, A2, A12, A16, JORDAN8:17, NAT_1:12;
now assume
i + 1
= len (Gauge C,n)
;
:: thesis: contradictionthen
(len (Gauge C,n)) -' 1
= i
by NAT_D:34;
then A19:
((Gauge C,n) * i,((width (Gauge C,n)) -' 1)) `1 = E-bound C
by A1, A2, A7, JORDAN8:15, NAT_D:35;
(NE-corner C) `1 >= (N-min C) `1
by PSCOMP_1:97;
hence
contradiction
by A13, A19, EUCLID:56;
:: thesis: verum end;
then
( i + 1 < len (Gauge C,n) & i < i + 1 )
by A16, NAT_1:13, XXREAL_0:1;
then
(N-min C) `1 <= ((Gauge C,n) * (i + 1),((width (Gauge C,n)) -' 1)) `1
by A14, A17;
then
N-min C in LSeg ((Gauge C,n) * i,((width (Gauge C,n)) -' 1)),((Gauge C,n) * (i + 1),((width (Gauge C,n)) -' 1))
by A13, A18, GOBOARD7:9;
hence
N-min C in cell (Gauge C,n),i,((width (Gauge C,n)) -' 1)
by A15; :: thesis: N-min C <> (Gauge C,n) * i,((width (Gauge C,n)) -' 1)
thus
N-min C <> (Gauge C,n) * i,((width (Gauge C,n)) -' 1)
by A13; :: thesis: verum