We consider the following Problem: Strict Trs: { b(b(y, z), c(a(), a(), a())) -> f(c(z, y, z)) , f(b(b(a(), z), c(a(), x, y))) -> z , c(y, x, f(z)) -> b(f(b(z, x)), z)} StartTerms: basic terms Strategy: innermost Certificate: YES(?,O(n^2)) Proof: We consider the following Problem: Strict Trs: { b(b(y, z), c(a(), a(), a())) -> f(c(z, y, z)) , f(b(b(a(), z), c(a(), x, y))) -> z , c(y, x, f(z)) -> b(f(b(z, x)), z)} StartTerms: basic terms Strategy: innermost Certificate: YES(?,O(n^2)) Proof: We consider the following Problem: Strict Trs: { b(b(y, z), c(a(), a(), a())) -> f(c(z, y, z)) , f(b(b(a(), z), c(a(), x, y))) -> z , c(y, x, f(z)) -> b(f(b(z, x)), z)} StartTerms: basic terms Strategy: innermost Certificate: YES(?,O(n^2)) Proof: The following argument positions are usable: Uargs(b) = {1}, Uargs(c) = {}, Uargs(f) = {1} We have the following constructor-based EDA-non-satisfying and IDA(2)-non-satisfying matrix interpretation: Interpretation Functions: b(x1, x2) = [1 0 1] x1 + [0 0 0] x2 + [0] [0 0 2] [0 0 0] [0] [0 0 1] [1 2 2] [1] c(x1, x2, x3) = [0 0 0] x1 + [0 0 0] x2 + [1 2 0] x3 + [0] [0 0 0] [0 0 0] [0 2 0] [0] [0 0 0] [0 0 0] [1 2 2] [0] a() = [0] [0] [0] f(x1) = [1 0 0] x1 + [0] [0 0 2] [2] [0 1 0] [0] Hurray, we answered YES(?,O(n^2))