let C be Simple_closed_curve; :: thesis: for i, j, k, n being Element of NAT st n is_sufficiently_large_for C & 1 <= k & k <= len (Span C,n) & [i,j] in Indices (Gauge C,n) & (Span C,n) /. k = (Gauge C,n) * i,j holds
i > 1
let i, j, k, n be Element of NAT ; :: thesis: ( n is_sufficiently_large_for C & 1 <= k & k <= len (Span C,n) & [i,j] in Indices (Gauge C,n) & (Span C,n) /. k = (Gauge C,n) * i,j implies i > 1 )
assume that
A1: n is_sufficiently_large_for C and
A2: ( 1 <= k & k <= len (Span C,n) ) and
A3: [i,j] in Indices (Gauge C,n) and
A4: (Span C,n) /. k = (Gauge C,n) * i,j ; :: thesis: i > 1
A5: ( 1 <= i & i <= len (Gauge C,n) & 1 <= j & j <= width (Gauge C,n) ) by A3, MATRIX_1:39;
len (Gauge C,n) = width (Gauge C,n) by JORDAN8:def 1;
then A6: ((Gauge C,n) * 2,j) `1 = W-bound C by A5, JORDAN8:14;
SpanStart C,n in BDD C by A1, Th7;
then A7: W-bound C <= W-bound (BDD C) by JORDAN1C:18;
A8: BDD C is Bounded by JORDAN2C:114;
then A9: Cl (BDD C) is compact by TOPREAL6:71, TOPREAL6:88;
A10: BDD C c= Cl (BDD C) by PRE_TOPC:48;
L~ (Span C,n) c= BDD C by A1, Th22;
then A11: W-bound (L~ (Span C,n)) >= W-bound (Cl (BDD C)) by A9, A10, PSCOMP_1:132, XBOOLE_1:1;
SpanStart C,n in BDD C by A1, Th7;
then A12: W-bound (BDD C) = W-bound (Cl (BDD C)) by A8, TOPREAL6:94;
len (Gauge C,n) >= 4 by JORDAN8:13;
then A13: len (Gauge C,n) >= 2 by XXREAL_0:2;
A14: len (Span C,n) > 4 by GOBOARD7:36;
k in dom (Span C,n) by A2, FINSEQ_3:27;
then (Span C,n) /. k in L~ (Span C,n) by A14, GOBOARD1:16, XXREAL_0:2;
then W-bound (L~ (Span C,n)) <= ((Gauge C,n) * i,j) `1 by A4, PSCOMP_1:71;
then W-bound (BDD C) <= ((Gauge C,n) * i,j) `1 by A11, A12, XXREAL_0:2;
then ((Gauge C,n) * 2,j) `1 <= ((Gauge C,n) * i,j) `1 by A6, A7, XXREAL_0:2;
then i >= 1 + 1 by A5, A13, GOBOARD5:4;
hence i > 1 by NAT_1:13; :: thesis: verum