Identify the radius of convergence from ordinary generating function

Question

Assume we have the ordinary generating function $f(x)$ of a series:

$f(x) = \tan x$

Can we identify the radius of convergence for this series?

Answer 1

$\textbf{Hint}$: The generating function of a sequence $\{f_n\}_{n=0}^{\infty}$ is defined as: $f(x) = \sum_{n=0}^{\infty} f_nx^n$.

$\bf{Additional}$