Here's how I would determine the number of times a prime number appears as a factor in a factorial: [: +/ ] <[EMAIL PROTECTED] [ ^ 1 + [: i. <[EMAIL PROTECTED]
Note that I "have to" use [: i. <[EMAIL PROTECTED] because i.@<[EMAIL PROTECTED] is not equivalent, even for scalar arguments. (Try this next example both ways to see what I mean.) For example: 5 factfact 1000000000000x 249999999997 I have not read this thread closely enough to know if someone has come up with a way of doing this for composite numbers, but since my answer agrees with Geoff Canyon's for this specific example, I declare our answer "correct". -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
