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Test the given series for convergence or divergence

Determine if the following series converges or diverges and justify your decision.

    \[ \sum_{n=2}^{\infty} \frac{1}{(\log n)^{\frac{1}{n}}}. \]


The series divergence by the comparison test. For n > 2 we have

    \begin{align*}  \log n > 1 && \implies && \log n &> \left( \log n )^{\frac{1}{n}} \\[9pt]  && \implies && \frac{1}{\log n} &< \frac{1}{(\log n)^{\frac{1}{n}}}. \end{align*}

Thus,

    \[ \sum_{n=2}^{\infty} \frac{1}{(\log  n)^{\frac{1}{n}}} > \sum_{n=2}^{\infty} \frac{1}{\log n} \]

which we know diverges. Hence, the given series diverges as well.

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