This is related to the the May 16 post, but takes only the prime indexed terms. Does it still diverge?

Hint

Transform the product into a sum


Hint

The harmonic series 1 + 1/2 + 1/3 + … 1/n +… diverges


  • siriusmart@lemmy.worldM
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    5 months ago

    I’ve shown that ln(n/n-1) is always larger than 1/n, so Σln(n/n-1) for all natural number n will be larger than the series 1+1/2+1/3+…

    but I don’t know how to make sure the sum of all ln(p/p-1) only when p is prime is larger than the provided series

    the question is strongly suggesting its divergent, i just dont know how to show it

    • EyeBeam@links.hackliberty.orgOP
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      5 months ago

      Perhaps surprisingly, that’s actually good enough since the sum of the prime reciprocals also diverges. However, I’m not letting you just assume that, and proving it is harder than the original problem.