Find the radius of convergence RRR for the series ∑n=0∞n!xn3n\sum_{n=0}^{\infty} \frac{n! x^n}{3^n}∑n=0∞3nn!xn.
R=0R = 0R=0
R=3R = 3R=3
R=1/3R = 1/3R=1/3
R=∞R = \inftyR=∞