YES (VAR x) (RULES half(0) -> 0 half(s(s(x))) -> s(half(x)) log(s(0)) -> 0 log(s(s(x))) -> s(log(s(half(x)))) ) The TRS is an overlay system and all critical pairs are trivial, thus termination of innermost rewriting is equivalent to termination of rewriting. Proving termination of innermost rewriting for _3_7: -> Dependency pairs: nF_half(s(s(x))) -> nF_half(x) nF_log(s(s(x))) -> nF_log(s(half(x))) nF_log(s(s(x))) -> nF_half(x) -> Proof of termination for _3_7_1_1: -> -> Dependency pairs in cycle: nF_log(s(s(x))) -> nF_log(s(half(x))) UsableRules: half(0) -> 0 half(s(s(x))) -> s(half(x)) Polynomial Interpretation: [half](X) = X [0] = 1 [s](X) = X + 1 [log](X) = 0 [nF_log](X) = X TIME: 4.1592e-2 -> Proof of termination for _3_7_1_2: -> -> Dependency pairs in cycle: nF_half(s(s(x))) -> nF_half(x) Termination proved: Cycles verify subterm criterion. SETTINGS: Base ordering: Polynomial ordering Proof mode: SCCs in DG + base ordering Upper bound for coeffs: 1 Rationals below 1 for all non-replacing args: No Polynomial interpretation: Linear Coeffs in polynomials: No rationals Delta: automatic Termination was proved succesfully.