Re: Factorials on the 86

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Re: Factorials on the 86

In article <gjohnson-ya02408000R1402980841110001@news.cjnetworks.com>
gjohnson@cjnetworks.com (Gene D Johnson) writes:
>In article <6c37vg$geq$1@hecate.umd.edu>, marshall@astro.umd.edu (James
>Marshall) wrote:

>>The definition I found in Schaum's Mathematical Handbook is:
>>
>>Gamma(n) = Integral( t^(n-1)*exp(-t), t, 0, infinity ) for n>0
>>
>>The book also has a graph of the Gamma function which includes negative
>>numbers, but I don't see a definition for how to get them with a quick
>>look at it.

>The fundamental identity for the Gamma function is Gamma(x + 1) = x*Gamma(x).
>
>This implies that Gamma(x) = Gamma(x + 1)/x.
>
>Using this version of the identity, you can get Gamma(x) for -1 < x < 0
>from the values of Gamma(x) for 0 < x < 1 (use the integral).  Repeat this
>process as needed to deal with any non-integer negative x.

Yes, you're right.  That's in the book also I must have just missed it
when I was looking last night.  It was nearing bed time.  :)

--
      .      .        .       .         -- James Marshall     (ORI)  *   ,
 ,.  -- )-- ,   , . -- )-- ,            marshall@astro.umd.edu
          '             '       http://www.astro.umd.edu/~marshall    '''
"Astronomy is a dyslexic's nightmare."                               ,   *
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