let I be non empty set ; for S being non empty FSM of I st S is calculating_type holds
for w1, w2 being FinSequence of I st w1 . 1 = w2 . 1 holds
GEN w1,the InitS of S, GEN w2,the InitS of S are_c=-comparable
let S be non empty FSM of I; ( S is calculating_type implies for w1, w2 being FinSequence of I st w1 . 1 = w2 . 1 holds
GEN w1,the InitS of S, GEN w2,the InitS of S are_c=-comparable )
assume A1:
S is calculating_type
; for w1, w2 being FinSequence of I st w1 . 1 = w2 . 1 holds
GEN w1,the InitS of S, GEN w2,the InitS of S are_c=-comparable
let w1, w2 be FinSequence of I; ( w1 . 1 = w2 . 1 implies GEN w1,the InitS of S, GEN w2,the InitS of S are_c=-comparable )
assume A2:
w1 . 1 = w2 . 1
; GEN w1,the InitS of S, GEN w2,the InitS of S are_c=-comparable
set A = (Seg (1 + (len w1))) /\ (Seg (1 + (len w2)));
( 1 + (len w1) <= 1 + (len w2) or 1 + (len w2) <= 1 + (len w1) )
;
then A3:
( ( Seg (1 + (len w1)) c= Seg (1 + (len w2)) & (Seg (1 + (len w1))) /\ (Seg (1 + (len w2))) = Seg (1 + (len w1)) ) or ( Seg (1 + (len w2)) c= Seg (1 + (len w1)) & (Seg (1 + (len w1))) /\ (Seg (1 + (len w2))) = Seg (1 + (len w2)) ) )
by FINSEQ_1:7, FINSEQ_1:9;
A4:
len (GEN w1,the InitS of S) = 1 + (len w1)
by FSM_1:def 2;
A5:
len (GEN w2,the InitS of S) = 1 + (len w2)
by FSM_1:def 2;
A6:
dom (GEN w1,the InitS of S) = Seg (1 + (len w1))
by A4, FINSEQ_1:def 3;
A7:
dom (GEN w2,the InitS of S) = Seg (1 + (len w2))
by A5, FINSEQ_1:def 3;
now let x be
set ;
( x in (Seg (1 + (len w1))) /\ (Seg (1 + (len w2))) implies (GEN w1,the InitS of S) . x = (GEN w2,the InitS of S) . x )assume A8:
x in (Seg (1 + (len w1))) /\ (Seg (1 + (len w2)))
;
(GEN w1,the InitS of S) . x = (GEN w2,the InitS of S) . xthen reconsider i =
x as
Element of
NAT ;
A9:
i >= 1
by A3, A8, FINSEQ_1:3;
A10:
i <= 1
+ (len w1)
by A3, A8, FINSEQ_1:3;
i <= 1
+ (len w2)
by A3, A8, FINSEQ_1:3;
hence
(GEN w1,the InitS of S) . x = (GEN w2,the InitS of S) . x
by A1, A2, A9, A10, Def1;
verum end;
hence
( GEN w1,the InitS of S c= GEN w2,the InitS of S or GEN w2,the InitS of S c= GEN w1,the InitS of S )
by A3, A6, A7, GRFUNC_1:8; XBOOLE_0:def 9 verum