let P1, P2 be Instruction-Sequence of SCMPDS; :: thesis: for s being 0 -started State of SCMPDS
for I being Program of st I is_closed_on s,P1 & I is_halting_on s,P1 & stop I c= P1 & stop I c= P2 holds
( LifeSpan (P1,s) = LifeSpan (P2,s) & Result (P1,s) = Result (P2,s) )

let s be 0 -started State of SCMPDS; :: thesis: for I being Program of st I is_closed_on s,P1 & I is_halting_on s,P1 & stop I c= P1 & stop I c= P2 holds
( LifeSpan (P1,s) = LifeSpan (P2,s) & Result (P1,s) = Result (P2,s) )

let I be Program of ; :: thesis: ( I is_closed_on s,P1 & I is_halting_on s,P1 & stop I c= P1 & stop I c= P2 implies ( LifeSpan (P1,s) = LifeSpan (P2,s) & Result (P1,s) = Result (P2,s) ) )
assume that
A1: I is_closed_on s,P1 and
A2: I is_halting_on s,P1 and
A3: stop I c= P1 and
A4: stop I c= P2 ; :: thesis: ( LifeSpan (P1,s) = LifeSpan (P2,s) & Result (P1,s) = Result (P2,s) )
A5: Start-At (0,SCMPDS) c= s by MEMSTR_0:29;
A6: Start-At (0,SCMPDS) c= s by MEMSTR_0:29;
DataPart s = DataPart s ;
then A7: I is_halting_on s,P2 by ;
A8: Initialize s = s by ;
A9: Initialize s = s by ;
P2 = P2 +* (stop I) by ;
then A10: P2 halts_on s by ;
P1 = P1 +* (stop I) by ;
then A11: P1 halts_on s by ;
A12: now :: thesis: for l being Nat st CurInstr (P2,(Comput (P2,s,l))) = halt SCMPDS holds
LifeSpan (P1,s) <= l
let l be Nat; :: thesis: ( CurInstr (P2,(Comput (P2,s,l))) = halt SCMPDS implies LifeSpan (P1,s) <= l )
assume A13: CurInstr (P2,(Comput (P2,s,l))) = halt SCMPDS ; :: thesis: LifeSpan (P1,s) <= l
CurInstr (P1,(Comput (P1,s,l))) = CurInstr (P2,(Comput (P2,s,l))) by A1, A3, A4, Th7;
hence LifeSpan (P1,s) <= l by ; :: thesis: verum
end;
CurInstr (P2,(Comput (P2,s,(LifeSpan (P1,s))))) = CurInstr (P1,(Comput (P1,s,(LifeSpan (P1,s))))) by A1, A3, A4, Th7
.= halt SCMPDS by ;
hence LifeSpan (P1,s) = LifeSpan (P2,s) by ; :: thesis: Result (P1,s) = Result (P2,s)
then A14: Result (P2,s) = Comput (P2,s,(LifeSpan (P1,s))) by ;
Result (P1,s) = Comput (P1,s,(LifeSpan (P1,s))) by ;
hence Result (P1,s) = Result (P2,s) by A1, A3, A4, A14, Th7; :: thesis: verum