YES (VAR x y z) (RULES g(x) -> b(f(s(x)),f(x)) u(b(x,0())) -> x u(b(x,s(y))) -> s(u(b(x,y))) p(x,y) -> u(b(x,y)) n(b(x,y)) -> b(u(b(x,y)),x) f(s(s(z))) -> u(b(f(s(z)),f(z))) f(s(0())) -> s(0()) f(0()) -> 0() ) (COMMENT Termination is shown by ELPO with interpretations on natural numbers p_A(x1,x2) = x1 0_A = 41379 s_A(x1) = x1 f_A(x1) = 41380 g_A(x1) = 41380 b_A(x1,x2) = x1 n_A(x1) = x1 u_A(x1) = x1 p#_A(x1,x2) = x2 0#_A = 0 s#_A(x1) = 0 f#_A(x1) = x1 g#_A(x1) = x1 n#_A(x1) = x1 u#_A(x1) = 0 and precedence: n > g > f > p > b > s > u > 0 )