%% This is based on the old Popper example.

pos(primorial(2)).
pos(primorial(6)).
pos(primorial(30)).
% pos(primorial(210)).

neg(primorial(1)).
neg(primorial(3)).
neg(primorial(4)).
neg(primorial(5)).
neg(primorial(7)).
% neg(primorial(12)). %% 2*3*2
% neg(primorial(18)). %% 2*3*3
neg(primorial(21)).
neg(primorial(211)).