YES Problem: f(f(a(),f(a(),a())),x) -> f(x,f(f(a(),a()),a())) Proof: DP Processor: DPs: f#(f(a(),f(a(),a())),x) -> f#(f(a(),a()),a()) f#(f(a(),f(a(),a())),x) -> f#(x,f(f(a(),a()),a())) TRS: f(f(a(),f(a(),a())),x) -> f(x,f(f(a(),a()),a())) Usable Rule Processor: DPs: f#(f(a(),f(a(),a())),x) -> f#(f(a(),a()),a()) f#(f(a(),f(a(),a())),x) -> f#(x,f(f(a(),a()),a())) TRS: Arctic Interpretation Processor: dimension: 1 usable rules: interpretation: [f#](x0, x1) = 1x0 + 2x1 + 4, [f](x0, x1) = 2x1, [a] = 0 orientation: f#(f(a(),f(a(),a())),x) = 2x + 5 >= 4 = f#(f(a(),a()),a()) f#(f(a(),f(a(),a())),x) = 2x + 5 >= 1x + 4 = f#(x,f(f(a(),a()),a())) problem: DPs: TRS: Qed