Solving Series: Does \sum_{n=1}^{\infty}\frac{1}{n^{1+\frac{1}{n}}} Converge?

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SUMMARY

The series \(\sum_{n=1}^{\infty}\frac{1}{n^{1+\frac{1}{n}}}\) diverges. By rewriting the series as \(\sum_{n=1}^{\infty}\frac{1}{n e^{\frac{1}{n} \ln n}}\) and applying the limit comparison test, it is established that \(\lim_{n\rightarrow\infty}\frac{1/ne^{\frac{1}{n}\ln n}}{1/n}=1\). Since the harmonic series \(\sum_{n=1}^{\infty}\frac{1}{n}\) diverges, the original series also diverges.

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Homework Statement



Determine whether the series converges or diverges.


[tex]\sum_{n=1}^{\infty}\frac{1}{n^{1+\frac{1}{n}}}[/tex]

The Attempt at a Solution



[tex]\sum_{n=1}^{\infty}\frac{1}{nn^{\frac{1}{n}}}=\sum_{n=1}^{\infty}\frac{1}{ne^{\frac{1}{n}\ln n}}[/tex]

[tex]\lim_{n\rightarrow\infty}\frac{\ln n}{n}=0[/tex]

[tex]\sum_{n=1}^{\infty}\frac{1}{ne^0}=\sum_{n=1}^{\infty}\frac{1}{n}[/tex]

Series diverges.
 
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Are you applying some form of the limit comparison test? If so, then you're right.
 
[tex]\lim_{n\rightarrow\infty}\frac{1/ne^{\frac{1}{n}\ln n}}{1/n}=1[/tex]

so both of them diverge
 

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