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  ANSI Common Lisp   12 Numbers   12.2 Dictionary of Numbers

12.2.34 lcm Function

Syntax:
lcm &rest integers    least-common-multiple

Arguments and Values:
integer - an integer.

least-common-multiple - a non-negative integer.

Description:
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)

Examples:
 (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

Exceptional Situations:
Should signal type-error if any argument is not an integer.

See Also:
gcd

Allegro CL Implementation Details:
None.

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