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Math Help - HELP PLEASE.....

  1. #1
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    HELP PLEASE.....

    Given that if n is a product of twin primes, say n = p(p+2), then
    φ(n)σ(n)=(n+1)(n-3)
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  2. #2
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    Quote Originally Posted by tret View Post
    Given that if n is a product of twin primes, say n = p(p+2), then
    φ(n)σ(n)=(n+1)(n-3)
    \phi(p(p+2)) = \phi (p)\phi(p+2)
    \sigma(p(p+2)) = \sigma (p) \sigma (p+2)

    Now use fact that \phi (q) = q-1, \sigma(q) = q+1 where q is prime.
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