YES TRS: first(0(),X) -> nil() first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) from(X) -> cons(X,n__from(s(X))) first(X1,X2) -> n__first(X1,X2) from(X) -> n__from(X) activate(n__first(X1,X2)) -> first(X1,X2) activate(n__from(X)) -> from(X) activate(X) -> X linear polynomial interpretations on N: first_A(x1,x2) = x2 + 4 first#_A(x1,x2) = x2 + 2 0_A = 1 0#_A = 1 nil_A = 0 nil#_A = 0 s_A(x1) = x1 + 1 s#_A(x1) = 0 cons_A(x1,x2) = x2 cons#_A(x1,x2) = 1 n__first_A(x1,x2) = x2 + 3 n__first#_A(x1,x2) = 0 activate_A(x1) = x1 + 1 activate#_A(x1) = x1 from_A(x1) = 4 from#_A(x1) = 2 n__from_A(x1) = 3 n__from#_A(x1) = 1 precedence: cons > n__first = activate > first = 0 = from > nil = s = n__from