YES TRS: active(terms(N)) -> mark(cons(recip(sqr(N)),terms(s(N)))) active(sqr(0())) -> mark(0()) active(sqr(s(X))) -> mark(s(add(sqr(X),dbl(X)))) active(dbl(0())) -> mark(0()) active(dbl(s(X))) -> mark(s(s(dbl(X)))) active(add(0(),X)) -> mark(X) active(add(s(X),Y)) -> mark(s(add(X,Y))) active(first(0(),X)) -> mark(nil()) active(first(s(X),cons(Y,Z))) -> mark(cons(Y,first(X,Z))) mark(terms(X)) -> active(terms(mark(X))) mark(cons(X1,X2)) -> active(cons(mark(X1),X2)) mark(recip(X)) -> active(recip(mark(X))) mark(sqr(X)) -> active(sqr(mark(X))) mark(s(X)) -> active(s(X)) mark(0()) -> active(0()) mark(add(X1,X2)) -> active(add(mark(X1),mark(X2))) mark(dbl(X)) -> active(dbl(mark(X))) mark(first(X1,X2)) -> active(first(mark(X1),mark(X2))) mark(nil()) -> active(nil()) terms(mark(X)) -> terms(X) terms(active(X)) -> terms(X) cons(mark(X1),X2) -> cons(X1,X2) cons(X1,mark(X2)) -> cons(X1,X2) cons(active(X1),X2) -> cons(X1,X2) cons(X1,active(X2)) -> cons(X1,X2) recip(mark(X)) -> recip(X) recip(active(X)) -> recip(X) sqr(mark(X)) -> sqr(X) sqr(active(X)) -> sqr(X) s(mark(X)) -> s(X) s(active(X)) -> s(X) add(mark(X1),X2) -> add(X1,X2) add(X1,mark(X2)) -> add(X1,X2) add(active(X1),X2) -> add(X1,X2) add(X1,active(X2)) -> add(X1,X2) dbl(mark(X)) -> dbl(X) dbl(active(X)) -> dbl(X) first(mark(X1),X2) -> first(X1,X2) first(X1,mark(X2)) -> first(X1,X2) first(active(X1),X2) -> first(X1,X2) first(X1,active(X2)) -> first(X1,X2) max/plus interpretations on N: active_A(x1) = max{53, x1} active#_A(x1) = max{120, 52 + x1} terms_A(x1) = max{235, 165 + x1} terms#_A(x1) = max{122, 123} mark_A(x1) = max{53, 41 + x1} mark#_A(x1) = max{119, 121 + x1} cons_A(x1,x2) = max{0, x1, 0} cons#_A(x1,x2) = max{118, 121, 66} recip_A(x1) = max{83, 13 + x1} recip#_A(x1) = max{204, 204} sqr_A(x1) = max{82, 40 + x1} sqr#_A(x1) = max{118, 132} s_A(x1) = max{3, 1} s#_A(x1) = max{54, 1} 0_A = 7 0#_A = 124 add_A(x1,x2) = max{141, x1, 71 + x2} add#_A(x1,x2) = max{0, 0, 0} dbl_A(x1) = max{11, x1} dbl#_A(x1) = max{130, 131} first_A(x1,x2) = max{140, 59 + x1, 70 + x2} first#_A(x1,x2) = max{115, 116, 117} nil_A = 54 nil#_A = 123 precedence: mark > recip > active > terms > s > sqr > add = dbl > 0 > nil > first > cons