Need some series/ summation help

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    Series Summation
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Discussion Overview

The discussion revolves around the convergence and potential closed form of the series \(\sum_{n=1}^{\infty}(-1)^{n}\frac{e^{-\frac{1}{nx}}}{n}\) for \(0

Discussion Character

  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant suggests that the series may have a closed form related to polylogarithms or Dirichlet eta functions.
  • Another participant claims that the series does not converge.
  • A different participant argues that the series does converge, stating it differs from a known convergent series by an absolutely convergent series.
  • One participant expresses skepticism about convergence, questioning the implications of raising \((-1)^n\) to the term \(\frac{e^{-\frac{1}{nx}}}{n}\).
  • Clarifications are made regarding the notation used in the series, emphasizing the correct interpretation of the summation term.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the convergence of the series, with multiple competing views presented regarding its behavior and representation.

Contextual Notes

There are unresolved questions regarding the convergence criteria and the implications of the series' structure, particularly concerning the treatment of the exponential term and the alternating series nature.

rman144
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[tex]\sum_{n=1}^{\infty}(-1)^{n}\frac{e^{-\frac{1}{nx}}}{n}[/tex]

Where 0<x<oo.

I'm looking for a closed form/ closed representation for this series [I was thinking something like a polylogarithm or dirichlet eta function combination might work].

Any ideas or suggestions would be much appreciated.
 
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it does not converge...
 
soandos said:
it does not converge...

Sure it does, it differs from [tex]\sum_{n=1}^\infty \frac{(-1)^n}{n}[/tex] by an absolutely convergent series.
 
If (-1)^n is being raised to [tex]\frac{e^{-\frac{1}{nx}}}{n}[/tex], i do not believe it converges. (it can also be simplified, the n's go away). please clarify what you mean.
 
I understand the confulsion. If you read the TeX code included, you can see what was actually written. The term to be summed is [itex](-1)^n[/itex] times a fraction:
[tex]\sum_{n=1}^{\infty}\;(-1)^{n}\left(\frac{e^{-\frac{1}{nx}}}{n}\right)[/tex]
 
g_edgar said:
I understand the confulsion. If you read the TeX code included, you can see what was actually written. The term to be summed is [itex](-1)^n[/itex] times a fraction:
[tex]\sum_{n=1}^{\infty}\;(-1)^{n}\left(\frac{e^{-\frac{1}{nx}}}{n}\right)[/tex]

Sorry about the confusion. I should have included the brackets as you demonstrated.
 

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