YES Problem: a(b(x1)) -> b(b(a(x1))) c(b(x1)) -> b(c(c(x1))) Proof: DP Processor: DPs: a#(b(x1)) -> a#(x1) c#(b(x1)) -> c#(x1) c#(b(x1)) -> c#(c(x1)) TRS: a(b(x1)) -> b(b(a(x1))) c(b(x1)) -> b(c(c(x1))) Matrix Interpretation Processor: dim=4 interpretation: [c#](x0) = [0 0 1 1]x0, [a#](x0) = [0 0 1 1]x0, [0 0 0 0] [0 0 0 0] [c](x0) = [0 0 1 0]x0 [0 0 0 1] , [0 0 0 0] [0 0 0 0] [a](x0) = [0 0 1 1]x0 [1 1 1 1] , [0 0 0 0] [0] [0 0 0 0] [0] [b](x0) = [0 0 0 1]x0 + [0] [1 1 1 0] [1] orientation: a#(b(x1)) = [1 1 1 1]x1 + [1] >= [0 0 1 1]x1 = a#(x1) c#(b(x1)) = [1 1 1 1]x1 + [1] >= [0 0 1 1]x1 = c#(x1) c#(b(x1)) = [1 1 1 1]x1 + [1] >= [0 0 1 1]x1 = c#(c(x1)) [0 0 0 0] [0] [0 0 0 0] [0] [0 0 0 0] [0] [0 0 0 0] [0] a(b(x1)) = [1 1 1 1]x1 + [1] >= [0 0 1 1]x1 + [1] = b(b(a(x1))) [1 1 1 1] [1] [1 1 1 1] [1] [0 0 0 0] [0] [0 0 0 0] [0] [0 0 0 0] [0] [0 0 0 0] [0] c(b(x1)) = [0 0 0 1]x1 + [0] >= [0 0 0 1]x1 + [0] = b(c(c(x1))) [1 1 1 0] [1] [0 0 1 0] [1] problem: DPs: TRS: a(b(x1)) -> b(b(a(x1))) c(b(x1)) -> b(c(c(x1))) Qed