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zetafunction
May15-09, 10:37 AM
where could i get some info about the function

\sum_{p} p^{-s}=P(s)

* the functional equation relating P(s) and P(1-s)

* the relation with Riemann zeta

Count Iblis
May15-09, 11:30 AM
You can express it as a summation over Riemann zeta's multiplied by a Möbius function. We have:

\zeta(s) = \sum_{r_{1},r_{2}\ldots}\prod_{j}p_{j}^{-sr_{j}}

where p_{j} is the jth prime and the r_{j} in the summation range from zero to infinity. Summing over the r_{j} gives:

\zeta(s)= \prod_{p}\frac{1}{1-p^{-s}}

Take the log of both sides:

\log\left[\zeta(s)\right]= -\sum_{p}\log\left(1-p^{-s}\right)

Expand the logarithm and sum over the primes p:

\log\left[\zeta(s)\right]=\sum_{k=1}^{\infty}\frac{P(ks)}{k}

You can then invert this relation to find the P(s) using Möbius inversion.

Count Iblis
May15-09, 12:30 PM
So, you find:

P(s) = \log\left[\zeta(s)\right] - \sum_{p}\frac{\log\left[\zeta(ps)\right]}{p} + \sum_{p_{1}<p_{2}}\frac{\log\left[\zeta(p_{1}p_{2}s)\right]}{p_{1}p_{2}}- \sum_{p_{1}<p_{2}<p_{3}}\frac{\log\left[\zeta(p_{1}p_{2}p_{3}s)\right]}{p_{1}p_{2}p_{3}}+\cdots

squidsoft
May16-09, 04:37 PM
I think P(s) as defined above by Count Iblis, can be written as

P(s)= \log \zeta(s)+\sum_{m=0}^{\infty}\sum_{n=1}^{\infty}(-1)^{m+1}\frac{\log\zeta\Big(s\prod_{k=0}^{m}p_{n+k }\Big)}{\prod_{k=0}^{m} p_{n+k}}.


I assume that's for \textnormal{Re}(s)>1.