(0) Obligation:
Generalized rewrite system (where rules with free variables on rhs are allowed):
The TRS R consists of the following rules:
2nd(cons(X)) → 2nd(cons1(X, X1))
2nd(cons1(X, cons(Y))) → Y
from(X) → cons(X)
(1) CritRuleProof (EQUIVALENT transformation)
The rule 2nd(cons(X)) → 2nd(cons1(X, X1)) contains free variables in its right-hand side. Hence the TRS is not-terminating.
(2) NO