Testing Convergence of Series: \Sigma^{\infty}_{n=1}\left[1/3^{ln\:n}}\right]

hobbes33
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\Sigma^{\infty}_{n=1}\left[1/3^{ln\:n}}\right]

How do I go about testing the convergence of this series?

I have no clue which method I should be using, since most tests fails on this one.

You don't have to show me everything, just a nudge in the right direction should get me going on this question :)
 
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Might help to know that 3^{\ln{n}}=3^{\frac{\log_{3}{n}}{\log_{3}{e}}}=n^\frac{1}{{\log_{3}{e}}}
 
zcd said:
Might help to know that 3^{\ln{n}}=3^{\frac{\log_{3}{n}}{\log_{3}{e}}}=n^\frac{1}{{\log_{3}{e}}}

Ah, here's the critical link. I got it, thanks! :D
 
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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