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Continuing series

  1. Nov 30, 2005 #1
    can u tell an appropriate method to prove this.

    Attached Files:

  2. jcsd
  3. Nov 30, 2005 #2

    matt grime

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    it'll be a lot easier if you type it out here in plain text or latexed mark up.
  4. Nov 30, 2005 #3
    The question as I see it is to show Sum(1/x), x=1 to n is never an integer. Well, take an example: Sum(1/x) x=1 to x=10 = 7381/2520. The factors of 7381 are 11^2x61, while the factors of 2520 are
    2^3x3^2x5x7, so it can not be an integer.

    From this example, you can proceed to find a general reason.
  5. Nov 30, 2005 #4


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    If you must attach a document please make it a PDF document. You can download Open Office here: http://www.openoffice.org/. It's free and it can open Microsoft Word Documents as well as being able to export to PDF. I also find its equation writer far more efficient and easy than Microsoft’s.

    But even more usefully, just learn this boards LaTeX: https://www.physicsforums.com/showthread.php?t=8997

    It allows you to quickly and easily write mathematical notation:

    [tex]1 + \frac{1}{2} + \frac{1}{3} + \ldots + \frac{1}{n}[/tex]

    Prove this is never an integer [itex]\forall \, n > 1[/itex]

    Anyway, robert has given sufficient help for you to start it.
    Last edited: Nov 30, 2005
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