MAYBE
LCTRS
  Theories
    Core, Ints
  Defines
    isEven: ((x Int)) Bool (= (mod x 2) 0)
  Sorts
    NList
  Signature
    build: (Int, NList) -> NList
    cons: (Int, NList) -> NList
    nats: NList
    nil: NList
  Rules
    nats -> build(0, nil)
    build(!n, !xs) -> build(+(!n, 1), cons(!n, !xs)) [and(isEven(!n), >=(!n, 0))]
    build(!n, !xs) -> build(+(!n, 1), !xs) [and(not(isEven(!n)), >=(!n, 0))]
No termination info given.

Elapsed Time:  54.14 ms