brun -s2 '(opt (com (q . (mod (N) (defun fact (N) (if (= N 1) 1 (* N (fact (- N 1))))) (fact N)))))'
(q 2 (q 2 2 (c 2 (c 5 ()))) (c (q 2 (i (= 5 (q . 1)) (q 1 . 1) (q 18 5 (a 2 (c 2 (c (- 5 (q . 1)) ()))))) 1) 1))
