let C be being_simple_closed_curve Subset of (TOP-REAL 2); (Y-InitStart C) + 1 < width (Gauge (C,(ApproxIndex C)))
set m = ApproxIndex C;
A1:
(X-SpanStart (C,(ApproxIndex C))) -' 1 <= len (Gauge (C,(ApproxIndex C)))
by JORDAN1H:50;
assume
(Y-InitStart C) + 1 >= width (Gauge (C,(ApproxIndex C)))
; contradiction
then A2:
( (Y-InitStart C) + 1 > width (Gauge (C,(ApproxIndex C))) or (Y-InitStart C) + 1 = width (Gauge (C,(ApproxIndex C))) )
by XXREAL_0:1;
A3:
( Y-InitStart C < width (Gauge (C,(ApproxIndex C))) or Y-InitStart C = width (Gauge (C,(ApproxIndex C))) )
by Def2;
per cases
( Y-InitStart C = width (Gauge (C,(ApproxIndex C))) or (Y-InitStart C) + 1 = width (Gauge (C,(ApproxIndex C))) )
by A2, A3, NAT_1:13;
suppose
(Y-InitStart C) + 1
= width (Gauge (C,(ApproxIndex C)))
;
contradictionthen
Y-InitStart C = (width (Gauge (C,(ApproxIndex C)))) -' 1
by NAT_D:34;
then A4:
cell (
(Gauge (C,(ApproxIndex C))),
((X-SpanStart (C,(ApproxIndex C))) -' 1),
((width (Gauge (C,(ApproxIndex C)))) -' 1))
c= BDD C
by Def2;
BDD C c= C `
by JORDAN2C:25;
then A5:
cell (
(Gauge (C,(ApproxIndex C))),
((X-SpanStart (C,(ApproxIndex C))) -' 1),
((width (Gauge (C,(ApproxIndex C)))) -' 1))
c= C `
by A4;
A6:
cell (
(Gauge (C,(ApproxIndex C))),
((X-SpanStart (C,(ApproxIndex C))) -' 1),
(width (Gauge (C,(ApproxIndex C)))))
c= UBD C
by A1, JORDAN1A:50;
set i1 =
X-SpanStart (
C,
(ApproxIndex C));
A7:
(X-SpanStart (C,(ApproxIndex C))) -' 1
<= X-SpanStart (
C,
(ApproxIndex C))
by NAT_D:44;
X-SpanStart (
C,
(ApproxIndex C))
< len (Gauge (C,(ApproxIndex C)))
by JORDAN1H:49;
then A8:
(X-SpanStart (C,(ApproxIndex C))) -' 1
< len (Gauge (C,(ApproxIndex C)))
by A7, XXREAL_0:2;
UBD C is_outside_component_of C
by JORDAN2C:68;
then A9:
UBD C is_a_component_of C `
by JORDAN2C:def 3;
(width (Gauge (C,(ApproxIndex C)))) -' 1
<= width (Gauge (C,(ApproxIndex C)))
by NAT_D:44;
then A10:
not
cell (
(Gauge (C,(ApproxIndex C))),
((X-SpanStart (C,(ApproxIndex C))) -' 1),
((width (Gauge (C,(ApproxIndex C)))) -' 1)) is
empty
by A1, JORDAN1A:24;
A11:
(width (Gauge (C,(ApproxIndex C)))) - 1
< width (Gauge (C,(ApproxIndex C)))
by XREAL_1:146;
A12:
1
<= (X-SpanStart (C,(ApproxIndex C))) -' 1
by JORDAN1H:50;
A13:
width (Gauge (C,(ApproxIndex C))) <> 0
by MATRIX_0:def 10;
then
((width (Gauge (C,(ApproxIndex C)))) -' 1) + 1
= width (Gauge (C,(ApproxIndex C)))
by NAT_1:14, XREAL_1:235;
then
(cell ((Gauge (C,(ApproxIndex C))),((X-SpanStart (C,(ApproxIndex C))) -' 1),(width (Gauge (C,(ApproxIndex C)))))) /\ (cell ((Gauge (C,(ApproxIndex C))),((X-SpanStart (C,(ApproxIndex C))) -' 1),((width (Gauge (C,(ApproxIndex C)))) -' 1))) = LSeg (
((Gauge (C,(ApproxIndex C))) * (((X-SpanStart (C,(ApproxIndex C))) -' 1),(width (Gauge (C,(ApproxIndex C)))))),
((Gauge (C,(ApproxIndex C))) * ((((X-SpanStart (C,(ApproxIndex C))) -' 1) + 1),(width (Gauge (C,(ApproxIndex C)))))))
by A8, A11, A12, GOBOARD5:26;
then A14:
cell (
(Gauge (C,(ApproxIndex C))),
((X-SpanStart (C,(ApproxIndex C))) -' 1),
(width (Gauge (C,(ApproxIndex C)))))
meets cell (
(Gauge (C,(ApproxIndex C))),
((X-SpanStart (C,(ApproxIndex C))) -' 1),
((width (Gauge (C,(ApproxIndex C)))) -' 1))
;
(width (Gauge (C,(ApproxIndex C)))) -' 1
< width (Gauge (C,(ApproxIndex C)))
by A13, A11, NAT_1:14, XREAL_1:233;
then
cell (
(Gauge (C,(ApproxIndex C))),
((X-SpanStart (C,(ApproxIndex C))) -' 1),
((width (Gauge (C,(ApproxIndex C)))) -' 1))
c= UBD C
by A6, A8, A14, A9, A5, GOBOARD9:4, JORDAN1A:25;
hence
contradiction
by A4, A10, JORDAN2C:24, XBOOLE_1:68;
verum end; end;