YES Problem: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) Proof: DP Processor: DPs: b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> b#(c(x1)) b#(a(a(x1))) -> a#(b(c(x1))) c#(a(x1)) -> c#(x1) c#(a(x1)) -> a#(c(x1)) c#(b(x1)) -> a#(x1) c#(b(x1)) -> b#(a(x1)) a#(a(x1)) -> b#(a(x1)) a#(a(x1)) -> a#(b(a(x1))) TRS: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) TDG Processor: DPs: b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> b#(c(x1)) b#(a(a(x1))) -> a#(b(c(x1))) c#(a(x1)) -> c#(x1) c#(a(x1)) -> a#(c(x1)) c#(b(x1)) -> a#(x1) c#(b(x1)) -> b#(a(x1)) a#(a(x1)) -> b#(a(x1)) a#(a(x1)) -> a#(b(a(x1))) TRS: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) graph: a#(a(x1)) -> a#(b(a(x1))) -> a#(a(x1)) -> a#(b(a(x1))) a#(a(x1)) -> a#(b(a(x1))) -> a#(a(x1)) -> b#(a(x1)) a#(a(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> a#(b(c(x1))) a#(a(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> b#(c(x1)) a#(a(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> c#(x1) c#(b(x1)) -> a#(x1) -> a#(a(x1)) -> a#(b(a(x1))) c#(b(x1)) -> a#(x1) -> a#(a(x1)) -> b#(a(x1)) c#(b(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> a#(b(c(x1))) c#(b(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> b#(c(x1)) c#(b(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> c#(x1) c#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> a#(b(a(x1))) c#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> b#(a(x1)) c#(a(x1)) -> c#(x1) -> c#(b(x1)) -> b#(a(x1)) c#(a(x1)) -> c#(x1) -> c#(b(x1)) -> a#(x1) c#(a(x1)) -> c#(x1) -> c#(a(x1)) -> a#(c(x1)) c#(a(x1)) -> c#(x1) -> c#(a(x1)) -> c#(x1) b#(a(a(x1))) -> a#(b(c(x1))) -> a#(a(x1)) -> a#(b(a(x1))) b#(a(a(x1))) -> a#(b(c(x1))) -> a#(a(x1)) -> b#(a(x1)) b#(a(a(x1))) -> c#(x1) -> c#(b(x1)) -> b#(a(x1)) b#(a(a(x1))) -> c#(x1) -> c#(b(x1)) -> a#(x1) b#(a(a(x1))) -> c#(x1) -> c#(a(x1)) -> a#(c(x1)) b#(a(a(x1))) -> c#(x1) -> c#(a(x1)) -> c#(x1) b#(a(a(x1))) -> b#(c(x1)) -> b#(a(a(x1))) -> a#(b(c(x1))) b#(a(a(x1))) -> b#(c(x1)) -> b#(a(a(x1))) -> b#(c(x1)) b#(a(a(x1))) -> b#(c(x1)) -> b#(a(a(x1))) -> c#(x1) Arctic Interpretation Processor: dimension: 1 usable rules: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) interpretation: [c#](x0) = 14x0, [b](x0) = x0 + 0, [b#](x0) = x0 + 0, [a#](x0) = x0 + 0, [a](x0) = 14x0 + 2, [c](x0) = 14x0 + 1 orientation: b#(a(a(x1))) = 28x1 + 16 >= 14x1 = c#(x1) b#(a(a(x1))) = 28x1 + 16 >= 14x1 + 1 = b#(c(x1)) b#(a(a(x1))) = 28x1 + 16 >= 14x1 + 1 = a#(b(c(x1))) c#(a(x1)) = 28x1 + 16 >= 14x1 = c#(x1) c#(a(x1)) = 28x1 + 16 >= 14x1 + 1 = a#(c(x1)) c#(b(x1)) = 14x1 + 14 >= x1 + 0 = a#(x1) c#(b(x1)) = 14x1 + 14 >= 14x1 + 2 = b#(a(x1)) a#(a(x1)) = 14x1 + 2 >= 14x1 + 2 = b#(a(x1)) a#(a(x1)) = 14x1 + 2 >= 14x1 + 2 = a#(b(a(x1))) b(a(a(x1))) = 28x1 + 16 >= 28x1 + 15 = a(b(c(x1))) c(a(x1)) = 28x1 + 16 >= 28x1 + 15 = a(c(x1)) c(b(x1)) = 14x1 + 14 >= 14x1 + 2 = b(a(x1)) a(a(x1)) = 28x1 + 16 >= 28x1 + 16 = a(b(a(x1))) problem: DPs: c#(b(x1)) -> b#(a(x1)) a#(a(x1)) -> b#(a(x1)) a#(a(x1)) -> a#(b(a(x1))) TRS: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) Restore Modifier: DPs: c#(b(x1)) -> b#(a(x1)) a#(a(x1)) -> b#(a(x1)) a#(a(x1)) -> a#(b(a(x1))) TRS: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) EDG Processor: DPs: c#(b(x1)) -> b#(a(x1)) a#(a(x1)) -> b#(a(x1)) a#(a(x1)) -> a#(b(a(x1))) TRS: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) graph: a#(a(x1)) -> a#(b(a(x1))) -> a#(a(x1)) -> b#(a(x1)) a#(a(x1)) -> a#(b(a(x1))) -> a#(a(x1)) -> a#(b(a(x1))) SCC Processor: #sccs: 1 #rules: 1 #arcs: 2/9 DPs: a#(a(x1)) -> a#(b(a(x1))) TRS: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) Arctic Interpretation Processor: dimension: 1 usable rules: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) interpretation: [b](x0) = -1x0 + 0, [a#](x0) = x0 + 0, [a](x0) = 1x0 + 1, [c](x0) = 1x0 + 1 orientation: a#(a(x1)) = 1x1 + 1 >= x1 + 0 = a#(b(a(x1))) b(a(a(x1))) = 1x1 + 1 >= 1x1 + 1 = a(b(c(x1))) c(a(x1)) = 2x1 + 2 >= 2x1 + 2 = a(c(x1)) c(b(x1)) = x1 + 1 >= x1 + 0 = b(a(x1)) a(a(x1)) = 2x1 + 2 >= 1x1 + 1 = a(b(a(x1))) problem: DPs: TRS: b(a(a(x1))) -> a(b(c(x1))) c(a(x1)) -> a(c(x1)) c(b(x1)) -> b(a(x1)) a(a(x1)) -> a(b(a(x1))) Qed