+
+;;; GCD
+(test (= 0 (gcd)))
+(test (= 6 (gcd 60 42)))
+(test (= 1 (gcd 3333 -33 101)))
+(test (= 11 (gcd 3333 -33 1002001)))
+(test (= 7 (gcd 91 -49)))
+(test (= 7 (gcd 63 -42 35)))
+(test (= 5 (gcd 5)))
+(test (= 4 (gcd -4)))
+
+;;; LCM
+(test (= 10 (lcm 10)))
+(test (= 150 (lcm 25 30)))
+(test (= 360 (lcm -24 18 10)))
+(test (= 70 (lcm 14 35)))
+(test (= 0 (lcm 0 5)))
+(test (= 60 (lcm 1 2 3 4 5 6)))