#1**+1 **

We can write \(15^{15}\) as \(3^{15} \times 5^{15}\)

Thus, n can be anything from 0 up to 15, making for \({16} \) values

EDIT: Upon furthur inspection, I found that n can also be 18, making for \(\color{brown}\boxed{17}\) values.

BuilderBoi Apr 30, 2022