prdel(1,[],_). prdel(P,[D|L],D):- prdel(P1,L,D). prdel(P,L,D):- D1 =< P, prdel(P,L,D1).
Standard input is empty
[[2, 2, 2, 3, 3], [2, 2, 2, 9], [2, 2, 3, 6], [2, 2, 18], [2, 3, 3, 4], [2, 3, 12], [2, 4, 9], [2, 6, 6], [2, 36], [3, 3, 8], [3, 4, 6], [3, 24], [4, 18], [6, 12], [8, 9], [72]]