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Sum is unique?

  1. Jun 11, 2006 #1
    if u have 3 primes: x,y,z
    then prove its sum m=x+y+z is unique ? Thank you
     
  2. jcsd
  3. Jun 11, 2006 #2

    matt grime

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    As stated it is a none question: given any three numbers there is a unique number that is their sum.
     
  4. Jun 11, 2006 #3
    Oh I stated probme incorectly,
    let x,y,z be primes, m=x+y+z
    Can u find other three primes that can sum to get m ? m can be any number.
     
  5. Jun 11, 2006 #4

    matt grime

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    Of course you can. You should try it. It's possible to find infinitely many counter examples, and there is a number less than 20 that is the sum of two primes in two different ways.
     
  6. Jun 11, 2006 #5

    Tide

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    Yes, but the question concerns three primes! :smile:
     
  7. Jun 11, 2006 #6

    shmoe

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    So add the same prime to both pairs.
     
  8. Jun 12, 2006 #7

    Tide

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    Of course. Nevermind! :blushing:
     
  9. Jun 21, 2006 #8
    I think that by other you have to find three totally different primes.

    This too is easy 3+13+31 = 7+11+29. Again, using 3 and 7, and two sets of twin primes. there are infinitely many examples assuming that their are infinitely many pairs of twin primes.
     
  10. Jun 22, 2006 #9
    If so, I think I can't go on solvin this problme
    Clearly a simple sum repeated day after day, trying to complicate the main porblme :rofl:
     
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