Certification Problem

Input (TPDB TRS_Outermost/Strategy_outermost_added_08/LengthOfFiniteLists_nosorts-noand_L)

The rewrite relation of the following TRS is considered.

U12(tt) s(length(L)) (1)
zeros cons(0) (2)
U11(tt) U12(tt) (3)
length(nil) 0 (4)
length(cons(N)) U11(tt) (5)
The evaluation strategy is outermost

Property / Task

Prove or disprove termination.

Answer / Result

No.

Proof (by AProVE @ termCOMP 2023)

1 Loop

The following loop proves nontermination.

t0 = U12(tt)
s(length(U12(tt)))
= t1
where t1 = C[t0] and C = s(length())