YES Problem: h(f(x,y)) -> f(y,f(h(h(x)),a())) Proof: DP Processor: DPs: h#(f(x,y)) -> h#(x) h#(f(x,y)) -> h#(h(x)) TRS: h(f(x,y)) -> f(y,f(h(h(x)),a())) Matrix Interpretation Processor: dim=2 interpretation: [h#](x0) = [0 1]x0, [0] [a] = [0], [0 3] [h](x0) = [1 0]x0, [0 0] [1 1] [1] [f](x0, x1) = [1 1]x0 + [0 0]x1 + [1] orientation: h#(f(x,y)) = [1 1]x + [1] >= [0 1]x = h#(x) h#(f(x,y)) = [1 1]x + [1] >= [1 0]x = h#(h(x)) [3 3] [0 0] [3] [3 3] [0 0] [3] h(f(x,y)) = [0 0]x + [1 1]y + [1] >= [0 0]x + [1 1]y + [1] = f(y,f(h(h(x)),a())) problem: DPs: TRS: h(f(x,y)) -> f(y,f(h(h(x)),a())) Qed