Re: Summations with Primes
- To: mathgroup at smc.vnet.net
- Subject: [mg39974] Re: Summations with Primes
- From: Olaf Rogalsky <Olaf.Rogalsky at physik.uni-erlangen.de>
- Date: Thu, 13 Mar 2003 03:04:22 -0500 (EST)
- Organization: University of Erlangen, Germany
- References: <b4mnus$imf$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Anthony Felder wrote:
>
> Can you tell me if, when calculating a summation of f(i) where i goes from
> imin to imax, Mathematica can be forced to only use prime values for i?
>
> Thank you for your time
>
> Anthony Felder
Sum[If[PrimeQ[i],f[i],0],{i,imin,imax}]
or better
Sum[f[Prime[i]], {i, PrimePi[imin-1]+1, PrimePi[imax]}]
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