YES Problem: a(b(x1)) -> x1 a(c(x1)) -> b(c(a(b(c(a(x1)))))) b(c(x1)) -> x1 Proof: DP Processor: DPs: a#(c(x1)) -> a#(x1) a#(c(x1)) -> b#(c(a(x1))) a#(c(x1)) -> a#(b(c(a(x1)))) a#(c(x1)) -> b#(c(a(b(c(a(x1)))))) TRS: a(b(x1)) -> x1 a(c(x1)) -> b(c(a(b(c(a(x1)))))) b(c(x1)) -> x1 Matrix Interpretation Processor: dim=1 interpretation: [b#](x0) = 0, [a#](x0) = x0, [c](x0) = 2x0 + 7, [a](x0) = 2x0 + 1/2, [b](x0) = 1/2x0 orientation: a#(c(x1)) = 2x1 + 7 >= x1 = a#(x1) a#(c(x1)) = 2x1 + 7 >= 0 = b#(c(a(x1))) a#(c(x1)) = 2x1 + 7 >= 2x1 + 4 = a#(b(c(a(x1)))) a#(c(x1)) = 2x1 + 7 >= 0 = b#(c(a(b(c(a(x1)))))) a(b(x1)) = x1 + 1/2 >= x1 = x1 a(c(x1)) = 4x1 + 29/2 >= 4x1 + 12 = b(c(a(b(c(a(x1)))))) b(c(x1)) = x1 + 7/2 >= x1 = x1 problem: DPs: TRS: a(b(x1)) -> x1 a(c(x1)) -> b(c(a(b(c(a(x1)))))) b(c(x1)) -> x1 Qed