MAYBE
Trs:
 { and(tt(), X) -> activate(X),
      x(N, 0()) -> 0(),
     x(N, s(M)) -> plus(x(N, M), N),
   plus(N, 0()) -> N,
  plus(N, s(M)) -> s(plus(N, M)),
    activate(X) -> X}
 Comment:
  We consider a duplicating trs.
  FAIL:
   Open