YES Problem: a(d(x1)) -> d(b(x1)) a(x1) -> b(b(b(x1))) b(d(b(x1))) -> a(c(x1)) c(x1) -> d(x1) Proof: DP Processor: DPs: a#(d(x1)) -> b#(x1) a#(x1) -> b#(x1) a#(x1) -> b#(b(x1)) a#(x1) -> b#(b(b(x1))) b#(d(b(x1))) -> c#(x1) b#(d(b(x1))) -> a#(c(x1)) TRS: a(d(x1)) -> d(b(x1)) a(x1) -> b(b(b(x1))) b(d(b(x1))) -> a(c(x1)) c(x1) -> d(x1) Matrix Interpretation Processor: dim=1 interpretation: [c#](x0) = 5x0 + 5/2, [b#](x0) = 2x0, [a#](x0) = 2x0 + 5/2, [c](x0) = 4x0, [b](x0) = x0 + 1/2, [a](x0) = x0 + 2, [d](x0) = 4x0 orientation: a#(d(x1)) = 8x1 + 5/2 >= 2x1 = b#(x1) a#(x1) = 2x1 + 5/2 >= 2x1 = b#(x1) a#(x1) = 2x1 + 5/2 >= 2x1 + 1 = b#(b(x1)) a#(x1) = 2x1 + 5/2 >= 2x1 + 2 = b#(b(b(x1))) b#(d(b(x1))) = 8x1 + 4 >= 5x1 + 5/2 = c#(x1) b#(d(b(x1))) = 8x1 + 4 >= 8x1 + 5/2 = a#(c(x1)) a(d(x1)) = 4x1 + 2 >= 4x1 + 2 = d(b(x1)) a(x1) = x1 + 2 >= x1 + 3/2 = b(b(b(x1))) b(d(b(x1))) = 4x1 + 5/2 >= 4x1 + 2 = a(c(x1)) c(x1) = 4x1 >= 4x1 = d(x1) problem: DPs: TRS: a(d(x1)) -> d(b(x1)) a(x1) -> b(b(b(x1))) b(d(b(x1))) -> a(c(x1)) c(x1) -> d(x1) Qed