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Math Help - prime number questions

  1. #1
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    prime number questions

    1)if p is bigger than 3 and prime,than prove p^2+pis prime.
    2) \forall{n}\in{N},2^{2^n}+1is prime prove.
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  2. #2
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    p^2+p is never prime, because it factorises as p(p+1).

    2^{2^5}+1 = 4294967297 = 641\times 6700417, so that is not prime either. It is not known whether there is any value of n greater than 4 for which the Fermat number 2^{2^n}+1 is prime.
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  3. #3
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    if p and {2^p}-1is prime then prove 2^{p-1}(2^p-{1}) is a perfect number.

    thanks fpr your helping,opalg
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  4. #4
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    Already done: Perfect Numbers

    For separate questions, please make new threads.
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  5. #5
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    ı am sorry guys ı am new on the site ı will be carefull
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