Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Prime number formula

  1. Apr 28, 2007 #1
    I was told by a math teacher I met recently that there is a formula that a mathematician in the 1800's came up with that accurately predicted all of the primes up to a certain point, but after that point began to miss a few primes, and after awhile, wasn't useful at all. Does anyone have any information on that?
     
  2. jcsd
  3. Apr 28, 2007 #2

    Office_Shredder

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    There is a polynomial in N that gives primes for something like n=1 through 79, but then falls apart. I can't remember what it is at the moment, but I'll try to find it if nobody else posts anything
     
  4. Apr 28, 2007 #3
    For some reason I'm recalling that it actually appears in Wittgenstein's Philosophical Investigations, but I'm not sure if that's right...
     
  5. Apr 29, 2007 #4

    Office_Shredder

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

  6. Apr 29, 2007 #5
    You can, of course, construct polynomials that will give you all the primes up to any arbitrary point, if you already know what they are!
     
  7. Apr 29, 2007 #6
    The positive solutions to the following system of equations are precisely the primes. But if you look closely you'll see that it's cheating you...

    0 = wz + h + j − q
    0 = (gk + 2g + k + 1)(h + j) + h − z
    0 = 16(k + 1)3(k + 2)(n + 1)2 + 1 − f2
    0 = 2n + p + q + z − e
    0 = e3(e + 2)(a + 1)2 + 1 − o2
    0 = (a2 − 1)y2 + 1 − x2
    0 = 16r2y4(a2 − 1) + 1 − u2
    0 = n + l + v − y
    0 = (a2 − 1)l2 + 1 − m2
    0 = ai + k + 1 − l − i
    0 = ((a + u2(u2 − a))2 − 1)(n + 4dy)2 + 1 − (x + cu)2
    0 = p + l(a − n − 1) + b(2an + 2a − n2 − 2n − 2) − m
    0 = q + y(a − p − 1) + s(2ap + 2p − p2 − 2p − 2) − x
    0 = z + pl(a − p) + t(2ap − p2 − 1) − pm.
     
  8. Apr 29, 2007 #7

    StatusX

    User Avatar
    Homework Helper

    Could you explain this?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Prime number formula
  1. Prime Number (Replies: 15)

  2. Prime numbers (Replies: 12)

  3. Prime numbers (Replies: 8)

Loading...