Suppose that an+1an1\displaystyle {\left|\frac{{a}_{{{n}+{1}}}}{{a}_{{n}}}\right|}\to{1} as n\displaystyle {n}\to\infty. Find the radius of convergence. n=1anxn6n\displaystyle {\sum_{{{n}={1}}}^{{\infty}}}\frac{{{a}_{{n}}{x}^{{n}}}}{{6}^{{n}}}