primes sieve from s s 0 from X cons X n__from s X head cons X Y X tail cons X Y activate Y if true X Y activate X if false X Y activate Y filter s s X cons Y Z if divides s s X Y n__filter s s X activate Z n__cons Y n__filter X sieve Y sieve cons X Y cons X n__filter X sieve activate Y from X n__from X filter X1 X2 n__filter X1 X2 cons X1 X2 n__cons X1 X2 activate n__from X from X activate n__filter X1 X2 filter X1 X2 activate n__cons X1 X2 cons X1 X2 activate X X primes 0 sieve 1 from 1 s 1 0 0 cons 2 n__from 1 head 1 tail 1 activate 1 if 3 true 0 false 0 filter 2 divides 2 n__filter 2 n__cons 2 FULL ./TRS/TRCSR/ExIntrod_GM99_Z.trs