It’s seen that, the initial term is \[\left( a \right)\text{ }=\text{ }1\]

What’s more, typical ratio\[\left( r \right)\text{ }=\text{ }4/1\text{ }=\text{ }4\]

We realize that, the overall term is

\[{{t}_{n}}~=\text{ }a{{r}^{n\text{ }\text{ }1}}\]

So,

\[{{t}_{9}}~=\text{ }\left( 1 \right){{\left( 4 \right)}^{9\text{ }\text{ }1}}~=\text{ }{{4}^{8~}}=\text{ }65536\]