Problem:
 from(X) -> cons(X,n__from(s(X)))
 length(n__nil()) -> 0()
 length(n__cons(X,Y)) -> s(length1(activate(Y)))
 length1(X) -> length(activate(X))
 from(X) -> n__from(X)
 nil() -> n__nil()
 cons(X1,X2) -> n__cons(X1,X2)
 activate(n__from(X)) -> from(X)
 activate(n__nil()) -> nil()
 activate(n__cons(X1,X2)) -> cons(X1,X2)
 activate(X) -> X

Proof:
 Unfolding Processor:
  loop length: 6
  terms:
   length(n__cons(X,n__from(x41887)))
   s(length1(activate(n__from(x41887))))
   s(length(activate(activate(n__from(x41887)))))
   s(length(activate(n__from(x41887))))
   s(length(from(x41887)))
   s(length(cons(x41887,n__from(s(x41887)))))
  context: s([])
  substitution:
   X -> x41887
   x41887 -> s(x41887)
  Qed