Convergence of sequence with log

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Homework Statement


prove that the series summation from n=3 to infinity of (1/(n*log(n)*(log(log(n))^p)) diverges if 0<p<=1 and converges for p>1.

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The Attempt at a Solution



2^n*a(2^n)= 1/(log(2^n)*(log(log(2^n))^p)). this is similar to the summation from n=2 to infinity of 1/(n(logn^p)) if we let n = log(2^n)...
 
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Try an integral test. Do the integral with a u substitution. What comes to mind?
 
we r not allowed to use integral tests. this is an analysis 1 class
 
l888l888l888 said:
we r not allowed to use integral tests. this is an analysis 1 class

I'm kind of surprised you don't have the integral test. It looks like you are trying to use the Cauchy condensation test. That's fine, but eventually you are going to get down to summing 1/n^p. Don't you need an integral test for that? Or were you just given that it diverges for p<=1 and converges for p>1?
 
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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