let n be Element of NAT ; for C being connected compact non horizontal non vertical Subset of (TOP-REAL 2)
for x, p being Point of (TOP-REAL 2) st x in E-most C & p in (east_halfline x) /\ (L~ (Cage C,n)) holds
p `1 = E-bound (L~ (Cage C,n))
let C be connected compact non horizontal non vertical Subset of (TOP-REAL 2); for x, p being Point of (TOP-REAL 2) st x in E-most C & p in (east_halfline x) /\ (L~ (Cage C,n)) holds
p `1 = E-bound (L~ (Cage C,n))
let x, p be Point of (TOP-REAL 2); ( x in E-most C & p in (east_halfline x) /\ (L~ (Cage C,n)) implies p `1 = E-bound (L~ (Cage C,n)) )
set G = Gauge C,n;
set f = Cage C,n;
A1:
Cage C,n is_sequence_on Gauge C,n
by JORDAN9:def 1;
assume A2:
x in E-most C
; ( not p in (east_halfline x) /\ (L~ (Cage C,n)) or p `1 = E-bound (L~ (Cage C,n)) )
then A3:
x in C
by XBOOLE_0:def 4;
A4:
(len (Gauge C,n)) -' 1 <= len (Gauge C,n)
by NAT_D:35;
A5:
len (Gauge C,n) = width (Gauge C,n)
by JORDAN8:def 1;
assume A6:
p in (east_halfline x) /\ (L~ (Cage C,n))
; p `1 = E-bound (L~ (Cage C,n))
then
p in L~ (Cage C,n)
by XBOOLE_0:def 4;
then consider i being Element of NAT such that
A7:
1 <= i
and
A8:
i + 1 <= len (Cage C,n)
and
A9:
p in LSeg (Cage C,n),i
by SPPOL_2:13;
A10:
LSeg (Cage C,n),i = LSeg ((Cage C,n) /. i),((Cage C,n) /. (i + 1))
by A7, A8, TOPREAL1:def 5;
A11:
i < len (Cage C,n)
by A8, NAT_1:13;
then
i in Seg (len (Cage C,n))
by A7, FINSEQ_1:3;
then
i in dom (Cage C,n)
by FINSEQ_1:def 3;
then consider i1, i2 being Element of NAT such that
A12:
[i1,i2] in Indices (Gauge C,n)
and
A13:
(Cage C,n) /. i = (Gauge C,n) * i1,i2
by A1, GOBOARD1:def 11;
A14:
( 1 <= i2 & i2 <= width (Gauge C,n) )
by A12, MATRIX_1:39;
p in east_halfline x
by A6, XBOOLE_0:def 4;
then
LSeg (Cage C,n),i is vertical
by A2, A7, A9, A11, Th100;
then
((Cage C,n) /. i) `1 = ((Cage C,n) /. (i + 1)) `1
by A10, SPPOL_1:37;
then A15:
p `1 = ((Cage C,n) /. i) `1
by A9, A10, GOBOARD7:5;
A16:
i1 <= len (Gauge C,n)
by A12, MATRIX_1:39;
A17:
1 <= i1
by A12, MATRIX_1:39;
x `1 =
(E-min C) `1
by A2, PSCOMP_1:108
.=
E-bound C
by EUCLID:56
.=
((Gauge C,n) * ((len (Gauge C,n)) -' 1),i2) `1
by A5, A14, JORDAN8:15
;
then
i1 > (len (Gauge C,n)) -' 1
by A3, A6, A13, A14, A17, A15, A4, Th96, SPRECT_3:25;
then
i1 >= ((len (Gauge C,n)) -' 1) + 1
by NAT_1:13;
then
i1 >= len (Gauge C,n)
by A17, XREAL_1:237, XXREAL_0:2;
then
i1 = len (Gauge C,n)
by A16, XXREAL_0:1;
then
(Cage C,n) /. i in E-most (L~ (Cage C,n))
by A7, A11, A13, A14, Th82;
hence
p `1 = E-bound (L~ (Cage C,n))
by A15, Th12; verum