MAYBE
LCTRS
  Theories
    Core, Ints
  Signature
    quad: Int -> Int
    twice: Int -> Int
    u: (Int, Int, Int) -> Int
  Rules
    quad(!x) -> +(twice(!x), twice(!x))
    u(!x, !i, !z) -> !z [not(<(!i, !x))]
    u(!x, !i, !z) -> u(!x, +(!i, 1), +(!z, 2)) [<(!i, !x)]
    twice(!x) -> u(!x, 0, 0)
No termination info given.

Elapsed Time:  39.44 ms