MathGroup Archive 2005

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Summation problem

  • To: mathgroup at smc.vnet.net
  • Subject: [mg56663] Re: Summation problem
  • From: Marcus Stollsteimer <marcus314 at yahoo.com>
  • Date: Tue, 3 May 2005 05:26:15 -0400 (EDT)
  • Organization: Comp.Center (RUS), U of Stuttgart, FRG
  • References: <d4v6br$nq9$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

jaropis wrote:

> Why can't Mathematica sum:
> Sum[I^n/n,{n,1,Infinity}]
> and gives the (incorrect) answer, that this is divergent while it
> can do: Sum[I^(n+1)/n,{n,1,Infinity}]
> correctly?

seems to be a new feature in 5.1 ...


In[1]:= Sum[I^n/n, {n, 1, Infinity}]
 
Sum::div: Sum does not converge.
 
Sum::div: Sum does not converge.
 
             n
            I
Out[1]= Sum[--, {n, 1, Infinity}]
            n
 
In[2]:= Sum[I^(n + 1)/n, {n, 1, Infinity}]
 
Out[2]= -I Log[1 - I]
 
In[3]:= $Version
 
Out[3]= 5.1 for Linux (October 25, 2004)


Regards,
Marcus

-- 
What is life but a series of inspired follies? -- George Bernard Shaw


  • Prev by Date: Re: Creating forms for user input in Mathematica
  • Next by Date: Re: Creating forms for user input in Mathematica
  • Previous by thread: Re: Summation problem
  • Next by thread: Re: Summation problem