lcm &rest integers ⇒ least-common-multiple
lcm returns the least common multiple of the integers.
If no integer is supplied, the integer 1 is returned.
If only one integer is supplied, the absolute value of that integer is returned.
For two arguments that are not both zero,
(lcm a b) ≡ (/ (abs (* a b)) (gcd a b))
If one or both arguments are zero,
(lcm a 0) ≡ (lcm 0 a) ≡ 0
For three or more arguments,
(lcm a b c ... z) ≡ (lcm (lcm a b) c ... z)
(lcm 10) ⇒ 10
(lcm 25 30) ⇒ 150
(lcm -24 18 10) ⇒ 360
(lcm 14 35) ⇒ 70
(lcm 0 5) ⇒ 0
(lcm 1 2 3 4 5 6) ⇒ 60
Should signal type-error if any argument is not an integer.