Convergence of a logaritmic series

Rono
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Homework Statement


Analyze the convergence of the following series, describing the criteria used:
\displaystyle\sum_{n=9}^{\infty}\frac{1}{(ln(ln(n)))^{ln(n)}}


Homework Equations


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The Attempt at a Solution


Wolfram Alpha says it converges due to comparison test, however I can't find to get a proper comparison. My main attempt was starting with \displaystyle ln(n)< n and, starting from there, getting:
(ln(ln(n)))^{ln(n)} < (ln(n))^{ln(n)} < n^{ln(n)} < n^{n}
However, after getting their reciprocal, I manage to prove \frac{1}{n^{n}} converges, but that is inconclusive. Any idea to which function I should start with to get the comparison test right?
 
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If you want to show it converges, then you need to replace \ln(\ln(n))^{\ln(n)} with something that is smaller than it, not larger. That means you need to think of a function which is smaller than ln(n) to replace some of those logs with.

It might help to remember that whenever there's a ln(n) in the exponent, you can do some algebra on it to rewrite your function!
 
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All right, managed to get \displaystyle ln(ln(n))^{ln(n)} = n^{ln(ln(ln(n)))}. Guess using n^{2} as the comparison function would work, right? Because at infinity, n^{ln(ln(ln(n)))} ≈ n^{n}, therefore I would it should converge.
 
I don't think that it looks anything close to nn but I agree that n2 is a good comparison.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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