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Math Help - factorizations

  1. #1
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    factorizations

    how to Find factorizations of 974!+2 by using algorithms
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  2. #2
    Super Member Bacterius's Avatar
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    I suspect this number has a lot of possible factorizations. You could use the elliptic curve factorization algorithm, it works remarkably smoothly for numbers with many possible factorizations.
    Or maybe there's some arithmetic trick to simplify this, I do not know.
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  3. #3
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    Quote Originally Posted by koko2009 View Post
    how to Find factorizations of 974!+2 by using algorithms
    It should be obvious that 2 is a factor.

     2 \left( \dfrac{974!}{2} + 1\right) = 974! + 2

    Test \left( \dfrac{974!}{2} + 1\right) for primality.

    Most likely it is a prime number.
    I did a Fermat test for several hundred primes.
    ALL results indicated that the number is prime.
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  4. #4
    Super Member Bacterius's Avatar
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    Try a Miller-Rabin test, maybe ? Or an AKS test to rub off doubts ...
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