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    First of all sorry if my LaTex use isn't very good,

    so using the formula:  2C_2 * n/log^{2}(n)

    with  C_2 = 0.660...
    to estimate the number of twin primes less than n

    When I put in  n = 100
    I get the estimate to be  6.2

    But when i cross check my answers with a website (link below) it says that for  n =100 the estimate of twin primes should be  15

    link: http://numbers.computation.free.fr/C...imes/twin.html

    Just confused with where I'm going wrong, can some one help?
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    (Original post by dom979)
    First of all sorry if my LaTex use isn't very good,

    so using the formula:  2C_2 * n/log^{2}(n)

    with  C_2 = 0.660...
    to estimate the number of twin primes less than n

    When I put in  n = 100
    I get the estimate to be  6.2

    But when i cross check my answers with a website (link below) it says that for  n =100 the estimate of twin primes should be  15

    link: http://numbers.computation.free.fr/C...imes/twin.html

    Just confused with where I'm going wrong, can some one help?
    If it is Log(n^2) then your answer will be 14.3317
    If you talk about Log[Log[n]]=Log^2(n) then answar will be 86.43 I dont know how you got 6.2

    Sorry if does not help
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    I believe that he got the 6.2 by taking the log part as (log n)^2. However I do not know much else about this problem.
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    (Original post by dom979)
    First of all sorry if my LaTex use isn't very good,

    so using the formula:  2C_2 * n/log^{2}(n)

    with  C_2 = 0.660...
    to estimate the number of twin primes less than n

    When I put in  n = 100
    I get the estimate to be  6.2

    But when i cross check my answers with a website (link below) it says that for  n =100 the estimate of twin primes should be  15

    link: http://numbers.computation.free.fr/C...imes/twin.html

    Just confused with where I'm going wrong, can some one help?
    Where have you got this formula from?

    The website you've linked to refers to the function Li_2(n) which is a logarithmic integral - it's not just the log of something (or even its square)!
 
 
 
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