Does the Series 1/[(ln(n))^ln(n)] Converge?

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Homework Help Overview

The discussion revolves around determining the convergence or divergence of the series given by the sum from n=2 to infinity of 1/[(ln(n))^ln(n)]. The subject area involves series convergence tests and logarithmic functions.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss using the comparison test, with one suggesting a comparison to the harmonic series and another proposing a comparison to 1/n^2. There is also mention of taking the logarithm of the ratio for analysis.

Discussion Status

The discussion is ongoing, with participants exploring different comparison strategies and raising questions about the setup of the series. Some guidance has been offered regarding the comparison test and the application of a specific theorem related to series convergence.

Contextual Notes

There is some ambiguity regarding the notation used in the original post, as one participant seeks clarification on the series definition. Additionally, the discussion includes references to established theorems that may influence the analysis.

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Homework Statement


Determine whether the series is convergent or divergent.

Sum from n=2 to n = infinity of

1/[(lnx)^lnx]

Homework Equations





The Attempt at a Solution



So far I've tried the comparison test, but all I can reach is that the series is less than the harmonic series, which of course doesn't help. Any help would be appreciated greatly, thanks.
 
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did you mean here

[tex]\sum_{n=2}^{\infty}\frac{1}{[ln(n)]^{ln(n)}}[/tex]
 
Let's try comparing it with 1/n^2. Remember, you can discard any finite number of terms when you do a comparison test. Try to figure out the limit n->infinity n^2/(log(n)^log(n)). Hint: take the log of the ratio.
 
There's a theorem said,
if a1>=a2>=...>=0, then [tex]\sum^{\infty}_{n=1}a_{n}[/tex] converges if and only if [tex]\sum^{\infty}_{k=0} 2^{k}a_{2^{k}}[/tex] converges.
This will make the original series to a better-looking one
 

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