Infinite Seriesmedium
0:00.0

Apply the Ratio Test to n=1n!2n(2n)!\sum_{n=1}^{\infty} \frac{n! \cdot 2^n}{(2n)!}. Compute limnan+1an\lim_{n \to \infty} \left|\frac{a_{n+1}}{a_n}\right|.