Does the sum of all series 1/n^m, m>1 converge?

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Discussion Overview

The discussion revolves around the convergence of the series defined by the sum of reciprocals raised to powers greater than one, specifically examining the double sum ##\sum_{m=2}^\infty \sum_{n=1}^\infty 1/n^m## and its behavior under different conditions. Participants explore both theoretical and computational aspects of convergence.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant states that the series ##\sum_{n=1}^\infty 1/n^2## converges to ##π^2/6## and questions the convergence of the double sum ##\sum_{m=2}^\infty \sum_{n=1}^\infty 1/n^m##.
  • Another participant argues that since every sum is greater than 1, the double sum would diverge, but raises the question of the behavior of partial sums.
  • A participant suggests that starting the inner sum at n=2 could yield interesting results and proposes that it converges to 1 based on computational results from Matlab.
  • There is a reiteration of interest in the convergence of the sum starting at n=2, with a participant providing numerical evidence for convergence towards 1.
  • One participant suggests flipping the sums to focus on the inner sum ##\sum_{m=2}^\infty 1/n^m## first.

Areas of Agreement / Disagreement

Participants express differing views on the convergence of the double sum, with some asserting divergence while others explore specific cases that suggest convergence. The discussion remains unresolved regarding the overall behavior of the sums.

Contextual Notes

Participants do not fully resolve the implications of their assumptions regarding the convergence of the sums, and there are indications of dependence on the starting points of the series.

BWV
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##\sum_{n=1}^\infty 1/n^2 ## converges to ##π^2/6##

and every other series with n to a power greater than 1 for n∈ℕ convergesis it known if the sum of all these series - ##\sum_{m=2}^\infty \sum_{n=1}^\infty 1/n^m ## for n∈ℕ converges?

apologies for any notational flaws
 
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Duh, so as every sum is >1 they of course the double sum above would diverge, but is there anything interesting about the partial sums or

##\sum_{m=2}^\infty \sum_{n=2}^\infty 1/n^m ## ?
 
A more interesting question is what is the result when the n sum starts at n=2.
 
mathman said:
A more interesting question is what is the result when the n sum starts at n=2.

Looks like it converges to 1

ran n to 2:1000 then 2:10000 in Matlab, n(1000)=0.9990, n(10,000)=0.9999
 
BWV said:
Duh, so as every sum is >1 they of course the double sum above would diverge, but is there anything interesting about the partial sums or

##\sum_{m=2}^\infty \sum_{n=2}^\infty 1/n^m ## ?
Flip the sums and focus on the ##\sum_{m=2}^\infty 1/n^m## part first.
 

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