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Homework Help: Infinite Product

  1. Jan 25, 2008 #1
    Essentially I need to find (if possible) the following infinite product

    [tex]1 - \frac{1}{2*n^{2}}[/tex]

    So, not quite Wallis number. I must say that I'm at a complete loss, not even sure where to begin.
  2. jcsd
  3. Jan 25, 2008 #2
    0.358486649396841... is approximately what the number is (thanks to Matlab).

    Looks like anything to you guys?
  4. Jan 25, 2008 #3


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    That looks awfully similar to the infinite product for sin z.
  5. Jan 25, 2008 #4
    Which is

    [tex]\sin(\pi\,z)=\pi\,z \prod_{n=1}^\infty\left(1-\frac{z^2}{n^2}\right)[/tex]

  6. Jan 25, 2008 #5
    I'm not familiar, what does it look like?
  7. Jan 25, 2008 #6
    Thanks guys =)
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