TRS: { a__primes() -> a__sieve(a__from(s(s(0())))), a__from(X) -> cons(mark(X), from(s(X))), a__head(cons(X, Y)) -> mark(X), a__tail(cons(X, Y)) -> mark(Y), a__if(true(), X, Y) -> mark(X), a__if(false(), X, Y) -> mark(Y), a__filter(s(s(X)), cons(Y, Z)) -> a__if(divides(s(s(mark(X))), mark(Y)), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))), a__sieve(cons(X, Y)) -> cons(mark(X), filter(X, sieve(Y))), mark(primes()) -> a__primes(), mark(sieve(X)) -> a__sieve(mark(X)), mark(from(X)) -> a__from(mark(X)), mark(head(X)) -> a__head(mark(X)), mark(tail(X)) -> a__tail(mark(X)), mark(if(X1, X2, X3)) -> a__if(mark(X1), X2, X3), mark(filter(X1, X2)) -> a__filter(mark(X1), mark(X2)), mark(s(X)) -> s(mark(X)), mark(0()) -> 0(), mark(cons(X1, X2)) -> cons(mark(X1), X2), mark(true()) -> true(), mark(false()) -> false(), mark(divides(X1, X2)) -> divides(mark(X1), mark(X2)), a__primes() -> primes(), a__sieve(X) -> sieve(X), a__from(X) -> from(X), a__head(X) -> head(X), a__tail(X) -> tail(X), a__if(X1, X2, X3) -> if(X1, X2, X3), a__filter(X1, X2) -> filter(X1, X2)} Fail