Heey...i got an expression that very much looks like a binomium- of newton. Not entirely though...

$\displaystyle \sum_{k=0}^n {n\choose k}(-a_0)^k\cdot \frac{t^{2n-k}}{(2n-k)!}$

I was thinking, is there any way to simplify this...? Write it as a power of some function.

Or do i need to accept its not gonna get simpler then this? :P

thank you