$a_n=\dfrac{27^n(n!)^3}{(3n)!}$
$\displaystyle\lim_{n\to\infty}\left|\, \frac{{{a}_{n+1}}}{{{a}_{n}}} \,\right|=$ [[☃ input-number 1]]
**Based on your answer, what does the ratio test say about $S=\displaystyle\sum_{n=1}^{\infty}a_n$?**
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