2 lcm - least common multiple of a set of rational numbers
8 x1, x2, ... rational number
10 return rational number
13 Compute the least common multiple of one or more rational numbers.
15 If no xi is zero, lcm(x1, x2, ...) is the least positive number v
16 for which v is a multiple of each xi. If at least one xi is zero,
20 > print lcm(12, -24, 30), lcm(9/10, 11/5, 4/25), lcm(2)
27 NUMBER *qlcm(NUMBER *x1, NUMBER *x2)