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Message Posted: Wed, 21 Sep 2005 @ 13:58:29 GMT

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If you are calculating small factorial's, multiplication is fine. However, if calculating large numbers, this can become difficult as the numbers get large quickly. If an approximation is fine (albeit a pretty good approximation as the numbers get fairly large), then you can use Stirling's Approximation

www.en.wikipedia.org/wiki/Stirling%27s_approximation

Basically:

     n! ~= sqrt(2*pi*n)*[(n/e)^n]

     where pi ~ 3.14159...
     and e ~ 2.718282

Dunno if this helps, but as a previous poster pointed out, for n>13, integers can't be used, and it doesn't take long until DECIMAL can't be used either (so FLOAT must be chosen to keep it in number format).

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