theorem Th29:
for
I being
Instruction of
SCM for
A being
Integer for
N being
Nat for
P being
Instruction-Sequence of
SCM st (
I = AddTo (
(dl. 2),
(dl. 1)) or
I = SubFrom (
(dl. 2),
(dl. 1)) or
I = MultBy (
(dl. 2),
(dl. 1)) ) &
IterativeAlgorithm I c= P holds
for
s being
0 -started State-consisting of
<%1,N,A%> holds
(
P halts_on s &
(Comput (P,s,1)) . (dl. 2) = A & ( for
k being
Nat st
0 < k &
k < N holds
IC (Comput (P,s,(4 * k))) = 5 ) & ( for
k being
Nat st
k < N holds
(
IC (Comput (P,s,((4 * k) + 1))) = 2 &
IC (Comput (P,s,((4 * k) + 2))) = 3 &
IC (Comput (P,s,((4 * k) + 3))) = 4 &
(Comput (P,s,((4 * k) + 1))) . (dl. 1) = N - k &
(Comput (P,s,((4 * k) + 2))) . (dl. 1) = N - k &
(Comput (P,s,((4 * k) + 3))) . (dl. 1) = (N - k) - 1 &
(Comput (P,s,((4 * k) + 4))) . (dl. 1) = (N - k) - 1 &
(Comput (P,s,(4 * k))) . (dl. 1) > 0 &
(Comput (P,s,((4 * k) + 1))) . (dl. 1) > 0 &
(Comput (P,s,((4 * k) + 2))) . (dl. 1) > 0 ) ) & (
N <> 0 implies (
LifeSpan (
P,
s)
= 4
* N & ( for
k,
j being
Nat st
k >= N holds
(
IC (Comput (P,s,((4 * k) + j))) = 1 &
(Comput (P,s,(((4 * k) + 1) + j))) . (dl. 1) = 0 ) ) ) ) )