let I be Instruction of S; ( I is sequential implies I is IC-relocable )
assume A1:
I is sequential
; I is IC-relocable
let j, k be Nat; AMISTD_2:def 3 for s being State of S holds (IC (Exec ((IncAddr (I,j)),s))) + k = IC (Exec ((IncAddr (I,(j + k))),(IncIC (s,k))))
let s1 be State of S; (IC (Exec ((IncAddr (I,j)),s1))) + k = IC (Exec ((IncAddr (I,(j + k))),(IncIC (s1,k))))
set s2 = IncIC (s1,k);
IC in dom ((IC ) .--> ((IC s1) + k))
by TARSKI:def 1;
then A2: IC (IncIC (s1,k)) =
((IC ) .--> ((IC s1) + k)) . (IC )
by FUNCT_4:13
.=
(IC s1) + k
by FUNCOP_1:72
;
A3: IC (Exec (I,(IncIC (s1,k)))) =
(IC (IncIC (s1,k))) + 1
by A1
.=
((IC s1) + 1) + k
by A2
;
A4:
IncAddr (I,j) = I
by A1, COMPOS_0:4;
IC (Exec (I,s1)) = (IC s1) + 1
by A1;
hence
(IC (Exec ((IncAddr (I,j)),s1))) + k = IC (Exec ((IncAddr (I,(j + k))),(IncIC (s1,k))))
by A1, A3, A4, COMPOS_0:4; verum