Termination w.r.t. Q of the given QTRS could be disproven:

(0) Obligation:

Q restricted rewrite system:
The TRS R consists of the following rules:

from(X) → cons(X)
length → 0
length → s(length1)
length1 → length

Q is empty.

(1) QTRS Reverse (EQUIVALENT transformation)

We applied the QTRS Reverse Processor [REVERSE].

(2) Obligation:

Q restricted rewrite system:
The TRS R consists of the following rules:

from(x) → cons(x)
length'(x) → 0'(x)
length'(x) → length1'(s(x))
length1'(x) → length'(x)

Q is empty.

(3) NonTerminationProof (EQUIVALENT transformation)

We used the non-termination processor [OPPELT08] to show that the SRS problem is infinite.

Found the self-embedding DerivationStructure:

length1' → length1' s

length1' → length1' s
by OverlapClosure OC 2

length1' → length'
by original rule (OC 1)

length' → length1' s
by original rule (OC 1)

(4) NO