I'm reviewing a text on Maclaurin series. This is more of an algebraic question, anyway. How do we go from here:
$$ z^2e^{3z} = \sum\limits_{n=0}^\infty \frac{z^2(3z)^n}{n!}$$
to here:
$$ z^2e^{3z} = \sum\limits_{n=0}^\infty \frac{z^n}{n!}z^{n+2} $$
It looks like 3^n became z^n. Is this possible?
