MAYBE
LCTRS
  Theories
    Core, Ints
  Sorts
    Unit
  Signature
    O: Unit
    ack: (Unit, Unit) -> Unit
    s: Unit -> Unit
  Rules
    ack(s(!m), s(!n)) -> ack(!m, ack(s(!m), !n))
    ack(s(!m), O) -> ack(!m, s(O))
    ack(O, !n) -> s(!n)
No termination info given.

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