Chapter 5.6, Problem 324E

Use the ratio test to determine whether ${\displaystyle \underset{n=1}{\overset{\infty }{\sum }}{a}_n}$converges,

where

$a_n$is given in the following problems. State if the ratio test is inconclusive.

324. ${\displaystyle \underset{n=1}{\overset{\infty }{\sum }}\frac{\left(2n\right)!}{{\left(2n\right)}^n}}$