>>865
lisp
(loop for a in '(1 4 3 4 5 6) for b in '(7 8 9 10 11 12) with n = 14 when (integerp (* (/ a b) n)) do (return (format t "a:~a b:~a" a b)) finally (princ "not found"))
a:1 b:7

(loop for a in '(1 4 3 4 5 6) for b in '(7 8 9 10 11 12) with n = 13 when (integerp (* (/ a b) n)) do (return (format t "a:~a b:~a" a b)) finally (princ "not found"))
not found