let C be Simple_closed_curve; for i being Element of NAT
for S being Segmentation of C st i in dom S holds
Segm S,i c= C
let i be Element of NAT ; for S being Segmentation of C st i in dom S holds
Segm S,i c= C
let S be Segmentation of C; ( i in dom S implies Segm S,i c= C )
assume
i in dom S
; Segm S,i c= C
then A1:
1 <= i
by FINSEQ_3:27;
( i < len S or i >= len S )
;
then
( Segm S,i = Segment (S /. i),(S /. (i + 1)),C or Segm S,i = Segment (S /. (len S)),(S /. 1),C )
by A1, Def4;
hence
Segm S,i c= C
by JORDAN16:10; verum