b a a x1 a b c x1 c a x1 a c x1 c b x1 b a x1 a a b x1 d b a x1 a d x1 d a x1 b d x1 a b x1 a a x1 a b a x1 b 1 a 1 c 1 d 1 FULL ./SRS/Zantema06/beans6.srs