YES O(n^2) TRS: {f(g(x, y), f(y, y)) -> f(g(y, x), y)} Natural interpretation: Strict: {f(g(x, y), f(y, y)) -> f(g(y, x), y)} Weak: {} Interpretation class: deltarestricted [g](delta, X1, X0) = + 1*X0 + 0*X1 + 0 + 0*X0*delta + 1*X1*delta + 0*delta [f](delta, X1, X0) = + 0*X0 + 0*X1 + 0 + 1*X0*delta + 1*X1*delta + 1*delta g_tau_1(delta) = delta/(0 + 1 * delta)g_tau_2(delta) = delta/(1 + 0 * delta) f_tau_1(delta) = delta/(0 + 1 * delta)f_tau_2(delta) = delta/(0 + 1 * delta) Qed