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Homework Help: Summation simplification help

  1. Jul 14, 2008 #1
    I am wondering whether the following expression can be simplified

    sum of( (p^n) / (n!) ) from n=1 to n=n.
  2. jcsd
  3. Jul 14, 2008 #2


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    Re: Summation

    It look pretty simple to me already. If you mean write it without the summation, I don't think so.
  4. Jul 14, 2008 #3


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    Re: Summation

    What do you mean by "n= n"? Did you mean
    [tex]\sum_{n=1}^{N} \frac{p^n}{n!}[/tex]?
    I don't see any simple way to write that. However, it is well known that
    [tex]\sum_{n=1}^\infty \frac{p^n}{n!}= e^p- 1[/tex]
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