let E be non empty set ; for F being Subset of (E ^omega)
for TS being non empty transition-system over F st not <%> E in rng (dom the Tran of TS) holds
for P being RedSequence of ==>.-relation TS
for k being Nat st k in dom P & k + 1 in dom P holds
(P . k) `2 <> (P . (k + 1)) `2
let F be Subset of (E ^omega); for TS being non empty transition-system over F st not <%> E in rng (dom the Tran of TS) holds
for P being RedSequence of ==>.-relation TS
for k being Nat st k in dom P & k + 1 in dom P holds
(P . k) `2 <> (P . (k + 1)) `2
let TS be non empty transition-system over F; ( not <%> E in rng (dom the Tran of TS) implies for P being RedSequence of ==>.-relation TS
for k being Nat st k in dom P & k + 1 in dom P holds
(P . k) `2 <> (P . (k + 1)) `2 )
assume A1:
not <%> E in rng (dom the Tran of TS)
; for P being RedSequence of ==>.-relation TS
for k being Nat st k in dom P & k + 1 in dom P holds
(P . k) `2 <> (P . (k + 1)) `2
let P be RedSequence of ==>.-relation TS; for k being Nat st k in dom P & k + 1 in dom P holds
(P . k) `2 <> (P . (k + 1)) `2
let k be Nat; ( k in dom P & k + 1 in dom P implies (P . k) `2 <> (P . (k + 1)) `2 )
assume A2:
( k in dom P & k + 1 in dom P )
; (P . k) `2 <> (P . (k + 1)) `2
consider s being Element of TS, u being Element of E ^omega , t being Element of TS, v being Element of E ^omega such that
A3:
P . k = [s,u]
and
A4:
P . (k + 1) = [t,v]
by A2, Th47;
[[s,u],[t,v]] in ==>.-relation TS
by A2, A3, A4, REWRITE1:def 2;
then
u <> v
by A1, Th43;
then
(P . k) `2 <> v
by A3;
hence
(P . k) `2 <> (P . (k + 1)) `2
by A4; verum