Re: Sum[1/(n^2 +n+1)^2,{n,1,p}]
- To: mathgroup at smc.vnet.net
- Subject: [mg8428] Re: [mg8344] Sum[1/(n^2 +n+1)^2,{n,1,p}]
- From: seanross at worldnet.att.net
- Date: Sat, 30 Aug 1997 00:42:37 -0400
- Sender: owner-wri-mathgroup at wolfram.com
w.meeussen wrote: > > a small request to those having Mma 3.0.1. : > > in my Mma 3.0.0. (Win'95) > the symbolic sum > Sum[1/(n^2 +n+1)^2,{n,1,p}] > works out to a v e r y impressive symbolic expression. > > But, setting p->1 or (any other integer) on the result yields no numeric output, > although it obviously should. > > How about the new release? > > wouter. > > Dr. Wouter L. J. MEEUSSEN > eu000949 at pophost.eunet.be > w.meeussen.vdmcc at vandemoortele.be On my Win95 pentium with Mma 3.0.1, Sum[1/(n^2 + n +1),{n,1,p}] returns a sum in terms of Polygamma and Tanh functions. Sum[1/(n^2 + n +1),{n,1,3}] returns a fraction 151/273. Sum[1/(n^2 + n +1)^2,{n,1,p}] returns a huge symbolic solution in terms of LerchPhi and Zeta functions. Sum[1/(n^2 + n +1)^2,{n,1,3}] returns a fraction 10243/74529. Sorry about the bug. I was told that there is a patch for Mma 3.0.0 by the folks at Wolfram. You'll need to call them up to get it. I hope it fixes the problem. Have you tried N[Sum[...?