let s1, s2 be State of ; for I being InitHalting Program of st Initialized I c= s1 & Initialized I c= s2 & s1,s2 equal_outside NAT holds
for k being Element of NAT holds
( Computation s1,k, Computation s2,k equal_outside NAT & CurInstr (Computation s1,k) = CurInstr (Computation s2,k) )
let I be InitHalting Program of ; ( Initialized I c= s1 & Initialized I c= s2 & s1,s2 equal_outside NAT implies for k being Element of NAT holds
( Computation s1,k, Computation s2,k equal_outside NAT & CurInstr (Computation s1,k) = CurInstr (Computation s2,k) ) )
assume that
A1:
Initialized I c= s1
and
A2:
Initialized I c= s2
and
A3:
s1,s2 equal_outside NAT
; for k being Element of NAT holds
( Computation s1,k, Computation s2,k equal_outside NAT & CurInstr (Computation s1,k) = CurInstr (Computation s2,k) )
A4:
I c= s2
by A2, SCM_HALT:13;
A5:
I c= s1
by A1, SCM_HALT:13;
hereby verum
let k be
Element of
NAT ;
( Computation s1,k, Computation s2,k equal_outside NAT & CurInstr (Computation s2,k) = CurInstr (Computation s1,k) )A6:
IC (Computation s1,k) in dom I
by A1, SCM_HALT:def 1;
A7:
IC (Computation s2,k) in dom I
by A2, SCM_HALT:def 1;
for
m being
Element of
NAT st
m < k holds
IC (Computation s2,m) in dom I
by A2, SCM_HALT:def 1;
hence
Computation s1,
k,
Computation s2,
k equal_outside NAT
by A3, A5, A4, SCMFSA6B:21;
CurInstr (Computation s2,k) = CurInstr (Computation s1,k)then A8:
IC (Computation s1,k) = IC (Computation s2,k)
by AMI_1:121;
thus CurInstr (Computation s2,k) =
s2 . (IC (Computation s2,k))
by AMI_1:54
.=
I . (IC (Computation s2,k))
by A4, A7, GRFUNC_1:8
.=
s1 . (IC (Computation s1,k))
by A5, A8, A6, GRFUNC_1:8
.=
CurInstr (Computation s1,k)
by AMI_1:54
;
verum
end;