Elementary arithmetic | Operations on numbers | Number theory
Least common multiple
In arithmetic and number theory, the least common multiple, lowest common multiple, or smallest common multiple of two integers a and b, usually denoted by lcm(a, b), is the smallest positive integer that is divisible by both a and b. Since division of integers by zero is undefined, this definition has meaning only if a and b are both different from zero. However, some authors define lcm(a,0) as 0 for all a, since 0 is the only common multiple of a and 0. The lcm is the "lowest common denominator" (lcd) that can be used before fractions can be added, subtracted or compared. The least common multiple of more than two integers a, b, c, . . . , usually denoted by lcm(a, b, c, . . .), is also well defined: It is the smallest positive integer that is divisible by each of a, b, c, . . . (Wikipedia).
