Finding the biggest possible value of n

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  1. Lord of the Flies's Avatar
    • The foul fiend Flibbertigibbet
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    Re: Finding the biggest possible value of n
    (Original post by MrBlueMo0n)
    Wowowowow! 1 is prime and 2 is prime? Or have I misread some of the comments?
    Who said 1 was prime?
  2. dantheman1261's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by MrBlueMo0n)
    Wowowowow! 1 is prime and 2 is prime? Or have I misread some of the comments?
    2 is prime.

    Is the question meant to be:

    "Find the largest value of n such that a^n+b^n=c^2 has a solution, where a, b and c are coprime integers"?
  3. Lord of the Flies's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by dantheman1261)
    2 is prime.

    Is the question meant to be:

    "Find the largest value of n such that a^n+b^n=c^2 has a solution, where a, b and c are coprime integers"?
    It's more restrictive: (a,b,c)\in\mathbb{P}
  4. MAA_96's Avatar
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    Re: Finding the biggest possible value of n
    Why this question is not Fermat's last theorem?
  5. Lord of the Flies's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by MAA_96)
    Why this question is not Fermat's last theorem?
    - Fermat's last theorem doesn't restrict a, b, c to primes

    - Fermat's last theorem doesn't restrict n to non-primes

    - Fermat's last theorem has three integers to the n, not two and one simply squared.
  6. MAA_96's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by Lord of the Flies)
    - Fermat's last theorem doesn't restrict a, b, c to primes

    - Fermat's last theorem doesn't restrict n to non-primes

    - Fermat's last theorem has three integers to the n, not two and one simply squared.
    But a,b,c being primes, all we get is 2+7=3^2, 2+23=5^2, 2+47=7^2, 2+167=13^2, etc., etc.

    :confused:
  7. Lord of the Flies's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by MAA_96)
    But a,b,c being primes, all we get is 2+7=3^2, 2+23=5^2, 2+47=7^2, 2+167=13^2, etc., etc.

    :confused:
    Not sure how that is a reply to my FLT post, but yes indeed I can't see any solutions for n>1 - so your answer is most probably 1, but I can't see a straightforward way of showing it (yet).
  8. danny111's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by MAA_96)
    1? could you explain your solution a little more please
    Dayum boy, you always assume n is even?
  9. MAA_96's Avatar
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    Re: Finding the biggest possible value of n
    Should n be even here ?
  10. MrBlueMo0n's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by Lord of the Flies)
    Who said 1 was prime?
    Millenhouse #3
  11. GreenLantern1's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by MrBlueMo0n)
    Wowowowow! 1 is prime and 2 is prime? Or have I misread some of the comments?
    1 is not prime.....look up the Fundamental Theorem of Arithmetic :facepalm:
  12. GreenLantern1's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by Lord of the Flies)
    Not sure how that is a reply to my FLT post, but yes indeed I can't see any solutions for n>1 - so your answer is most probably 1, but I can't see a straightforward way of showing it (yet).
    Doesn't the modular arithmetic cases show that the congruence of c^2 to 6 can never be the same for the congruence of a^n +b^n to 6 for n>1 ?
  13. moritzplatz's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by MrBlueMo0n)
    Wowowowow! 1 is prime and 2 is prime? Or have I misread some of the comments?
    2 is prime 1 is not.
  14. Lord of the Flies's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by GreenLantern1)
    Doesn't the modular arithmetic cases show that the congruence of c^2 to 6 can never be the same for the congruence of a^n +b^n to 6 for n>1 ?
    Not when (a,b)=(2,3) - I posted something about this earlier; if n is even:

    2^n+3^n\equiv 1\pmod{6}

    c^2\equiv 1\pmod{6}
    Last edited by Lord of the Flies; 12-07-2012 at 15:17.
  15. GreenLantern1's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by Lord of the Flies)
    Not when (a,b)=(2,3) - I posted something about this earlier; if n is even:

    2^n+3^n=1\pmod{6}

    c^2=1\pmod{6}
    Oh I thought it was mentioned that 2 and 3 were not inclusive. Oh it must have been you saying that you could prove it when excluding 2 and 3.
  16. GreenLantern1's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by Lord of the Flies)
    Not when (a,b)=(2,3) - I posted something about this earlier; if n is even:

    2^n+3^n=1\pmod{6}

    c^2=1\pmod{6}
    And not to be pedantic but you should be using the congruence sign rather than the equal sign for modular arithmetic...
  17. Lord of the Flies's Avatar
    • The foul fiend Flibbertigibbet
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    Re: Finding the biggest possible value of n
    (Original post by GreenLantern1)
    And not to be pedantic but you should be using the congruence sign rather than the equal sign for modular arithmetic...
    Just a typo - I know what a congruence is

    Edit: corrected now
    Last edited by Lord of the Flies; 12-07-2012 at 15:23.
  18. GreenLantern1's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by Lord of the Flies)
    Just a typo - I know what a congruence is

    Edit: corrected now
    Well since you showed the cases of congruence I am sure you do! Just thought I'd let you know
  19. MrBlueMo0n's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by GreenLantern1)
    1 is not prime.....look up the Fundamental Theorem of Arithmetic :facepalm:
    I know, but some guy said that 1 was prime. Don't really remember why I put '2 is prime?' in there as well, but I did get confused with the 1...
  20. MrBlueMo0n's Avatar
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    Re: Finding the biggest possible value of n
    (Original post by moritzplatz)
    2 is prime 1 is not.
    TY
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