Convergence of Series with Logarithmic Terms

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    Convergence Series
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SUMMARY

The series $\sum\limits_{n = 2}^{\infty}\frac{1}{(\ln n)^{\ln n}}$ converges. The transformation $\frac{1}{(\ln n)^{\ln n}} = \frac{1}{e^{\ln n \ln(\ln n)}}$ reveals that as \( n \) increases, \( \ln(\ln n) \) exceeds 2, leading to a rapid growth in the denominator. This growth ensures that the terms of the series approach zero sufficiently quickly, confirming convergence through the comparison test with a known convergent series.

PREREQUISITES
  • Understanding of series convergence tests, particularly the comparison test.
  • Familiarity with logarithmic functions and their properties.
  • Knowledge of limits and asymptotic behavior of functions.
  • Basic calculus concepts, including infinite series.
NEXT STEPS
  • Study the comparison test for series convergence in detail.
  • Learn about the properties of logarithmic functions and their growth rates.
  • Explore the concept of asymptotic notation and its applications in series analysis.
  • Investigate other series involving logarithmic terms, such as $\sum\limits_{n=1}^{\infty} \frac{1}{n (\ln n)^p}$ for various values of \( p \).
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Mathematicians, students studying advanced calculus, and anyone interested in the convergence properties of series involving logarithmic terms.

Dustinsfl
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$\sum\limits_{n = 2}^{\infty}\frac{1}{(\ln n)^{\ln n}}$

I am trying to show that this series diverges or converges
 
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dwsmith said:
$\sum\limits_{n = 2}^{\infty}\frac{1}{(\ln n)^{\ln n}}$

I am trying to show that this series diverges or converges
Hint: $\displaystyle\frac{1}{(\ln n)^{\ln n}} = \frac{1}{e^{\ln n \ln(\ln n)}}$, and if $n$ is large enough then $\ln(\ln n)>2$.
 

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