Hey, I've come across the following limit when trying to solve a problem in probability:

$\displaystyle $$ \lim_{ n \to \infty} e^{-(\sqrt{n\cdot m})it} \left(1- \frac{m}{n}(1-e^{it/\sqrt{n\cdot m}}) \right)^{n^2}$$$

Would appreciate any help!

(I believe it should approach the characteristic function for a normal distribution: $\displaystyle $$e^{-t^2/2} $$$)