let h be non constant standard special_circular_sequence; :: thesis:
set i1 = n_e_n h;
set i2 = n_e_s h;
A1: n_e_n h <= () + 1 by NAT_1:11;
A2: 1 <= n_e_n h by Def16;
(n_e_n h) + 1 <= len h by Def16;
then n_e_n h <= len h by ;
then n_e_n h in dom h by ;
then A3: h . () = h /. () by PARTFUN1:def 6;
A4: n_e_s h <= () + 1 by NAT_1:11;
A5: h . () = S-max (L~ h) by Def14;
A6: 1 <= n_e_s h by Def14;
(n_e_s h) + 1 <= len h by Def14;
then n_e_s h <= len h by ;
then n_e_s h in dom h by ;
then A7: h . () = h /. () by PARTFUN1:def 6;
A8: h . () = N-max (L~ h) by Def16;
thus n_e_n h <> n_e_s h :: thesis: verum
proof
assume n_e_n h = n_e_s h ; :: thesis: contradiction
then A9: N-bound (L~ h) = (h /. ()) `2 by
.= S-bound (L~ h) by ;
A10: 1 <= len h by ;
then A11: (h /. 1) `2 >= S-bound (L~ h) by Th11;
consider ii being Nat such that
A12: ii in dom h and
A13: (h /. ii) `2 <> (h /. 1) `2 by GOBOARD7:31;
A14: ii <= len h by ;
A15: 1 <= ii by ;
then A16: (h /. ii) `2 <= N-bound (L~ h) by ;
A17: (h /. ii) `2 >= S-bound (L~ h) by ;
(h /. 1) `2 <= N-bound (L~ h) by ;
then (h /. 1) `2 = N-bound (L~ h) by ;
hence contradiction by A9, A13, A16, A17, XXREAL_0:1; :: thesis: verum
end;