MAYBE

'Pop* with parameter subtitution (timeout of 60.0 seconds)'
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Answer:           MAYBE
Input Problem:    innermost runtime-complexity with respect to
  Rules:
    {  digits() -> d(0())
     , d(x) -> if(le(x, s(s(s(s(s(s(s(s(s(0())))))))))), x)
     , if(true(), x) -> cons(x, d(s(x)))
     , if(false(), x) -> nil()
     , le(0(), y) -> true()
     , le(s(x), 0()) -> false()
     , le(s(x), s(y)) -> le(x, y)}

Proof Output:    
  The input cannot be shown compatible