Path: utzoo!mnetor!uunet!husc6!uwvax!dogie!uwmcsd1!csd4.milw.wisc.edu!markh
From: markh@csd4.milw.wisc.edu (Mark William Hopkins)
Newsgroups: sci.misc
Subject: Re: Formulae
Message-ID: <5298@uwmcsd1.UUCP>
Date: 22 Mar 88 02:23:56 GMT
References: <172@wjh12.harvard.edu>
Sender: daemon@uwmcsd1.UUCP
Reply-To: markh@csd4.milw.wisc.edu (Mark William Hopkins)
Organization: University of Wisconsin-Milwaukee
Lines: 24
Summary: The inverse of the exponential series.

In article <172@wjh12.harvard.edu> lotto@wjh12.UUCP (Jerry Lotto) writes:
>
>I am surprised that noone has mentioned that:
>
>	f  x
>	| e  = F(u,n)
>	j
>

Well, here is one that not too many people are aware of:

The exponential series formula (pardon my infinity symbol 00)

         x    OO     n
	e  = SUM    x / n!
            n = 0  

has an inverse:

                00     n   x
	n! = INTEGRAL x / e  dx
               x = 0

(related to the Gamma function, for those who know about it.)