YES TRS: f(x,c(y)) -> f(x,s(f(y,y))) f(s(x),y) -> f(x,s(c(y))) max/plus interpretations on N: f_A(x1,x2) = max{12, 9, 11 + x2} f#_A(x1,x2) = max{2, 2, x2} c_A(x1) = max{3, 6 + x1} c#_A(x1) = max{2, 2} s_A(x1) = max{1, 1} s#_A(x1) = max{2, -7 + x1} precedence: f > c > s