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What 5 Numbers; Including 0, 2 Even And 2 Odd For A Formula That Yields Prime Numbers?

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    If you have a formula that supposedly yields prime numbers, the idea here is to check to see if it really does. You are to pick 5 numbers to try in the formula. An easy choice meeting the required conditions might be
      0    (you must include 0)
      1    (odd)
      2    (even)
      3    (odd)
      4    (even)
    This list (above) has 2 odd, 2 even, and 0. It might be more interesting to try some numbers farther apart. For example, you might want to try
      0    (you must include 0)
      22    (even)
      51    (odd)
      64    (even)
      75    (odd)

    If the formula is
      F(x) = x2 + x + 41
    then
      F(22) = 222 + 22 + 41 = 484 + 22 + 41 = 506 + 41 = 547
    This table shows 547 to be prime.
      F(51) = 512 + 51 + 41 = 2693 (prime)
      F(64) = 642 + 64 + 41 = 4201 (prime)
      F(75) = 752 + 75 + 41 = 5741 (prime)
    As suggested in another answer, you could also check x=41.
      F(41) = 412 + 41 + 41 = 1763 = 41*43 (not prime)
    I just made up the above numbers. I am somewhat surprised to see they all (except 41) give primes.
    0 0

    Oddman 

    answered 5 months ago

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