;(mod (arg_one)
;  (defun factorial (input)
;    (if (= input 1) 1 (* (factorial (- input 1)) input))
;  )
;  (factorial arg_one)
;)

(a (q 2 2 (c 2 (c 5 (q)))) (c (q 2 (i (= 5 (q . 1)) (q 1 . 1) (q 18 (a 2 (c 2 (c (- 5 (q . 1)) (q)))) 5)) 1) 1))