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Math Help - Another problem....

  1. #1
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    Another problem....

    If the prime number "a" is larger than 10^5 what is the sum of the multiples of a? This is a math Olympiad question.
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  2. #2
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    Re: Another problem....

    Surely it would be infinity...
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  3. #3
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    Re: Another problem....

    The answers do not include infinty...it's multiple choice.

    The answers are one of the following:

    a+5
    a+2
    a+1
    10^5-a

    I need to know which answer with proof.
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  4. #4
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    Re: Another problem....

    er...it's actually the sum of the common denominators not the multiples..my bad.
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  5. #5
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    Re: Another problem....

    As stated, I would find:

    S=\frac{a}{2}\lim_{n\to\infty}n^2+2=\infty
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  6. #6
    MHF Contributor MarkFL's Avatar
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    Re: Another problem....

    Do you mean the sum of the divisors?
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  7. #7
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    Re: Another problem....

    please clarify your question, sum of divisors of a prime number would be no sense, and the multiples of every number go to infinity.Are you sure that's the question?
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