Certification Problem
Input (TPDB TRS_Standard/Transformed_CSR_04/Ex4_7_56_Bor03_L)
The rewrite relation of the following TRS is considered.
after
(
s
(
N
),
cons
(
X
))
→
after
(
N
,
XS
)
(1)
from
(
X
)
→
cons
(
X
)
(2)
after
(
0
,
XS
)
→
XS
(3)
Property / Task
Prove or disprove termination.
Answer / Result
No.
Proof (by ttt2 @ termCOMP 2023)
1 Loop
The following loop proves nontermination.
t
0
=
after
(
s
(
N
),
cons
(
X
))
→
after
(
N
,
after
(
s
(
N
),
cons
(
X
)))
=
t
1
where t
1
= C[t
0
σ] and σ = {
XS
/
after
(
s
(
N
),
cons
(
X
))} and C =
after
(
N
,
☐
)