YES TRS: fib(0()) -> 0() fib(s(0())) -> s(0()) fib(s(s(0()))) -> s(0()) fib(s(s(x))) -> sp(g(x)) g(0()) -> pair(s(0()),0()) g(s(0())) -> pair(s(0()),s(0())) g(s(x)) -> np(g(x)) sp(pair(x,y)) -> +(x,y) np(pair(x,y)) -> pair(+(x,y),x) +(x,0()) -> x +(x,s(y)) -> s(+(x,y)) max/plus interpretations on N: fib_A(x1) = max{9, 0} fib#_A(x1) = max{3, 3 + x1} 0_A = 1 0#_A = 5 s_A(x1) = max{6, 3} s#_A(x1) = max{0, 4} sp_A(x1) = max{5, 9 + x1} sp#_A(x1) = max{5, 2 + x1} g_A(x1) = max{0, -9} g#_A(x1) = max{8, 2} pair_A(x1,x2) = max{0, -6 + x1, -7} pair#_A(x1,x2) = max{6, 5, 6} np_A(x1) = max{0, x1} np#_A(x1) = max{1, 7} +_A(x1,x2) = max{6, x1, 3} +#_A(x1,x2) = max{4, 4, -6} precedence: g = np > 0 = sp = pair > fib = + > s