Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Power series

  1. Sep 10, 2008 #1
    I'm trying to find the sum of the following series and am a bit stuck:

    sum_{r=0}^{+\infty}1/(r*r!)

    It looks a bit like e^1 but the extra r in the denominator is causing problems. Can anyone help?
     
  2. jcsd
  3. Sep 10, 2008 #2
    Where does this problem originates from?
     
  4. Sep 11, 2008 #3
    It's part of a birth rate for a birth and death process in a particular special case. The series looks like it should be summable but I can't think how to do it.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook




Loading...