Removing recursion from sequence

I think this is the right section since sequences belong to discrete math. Anyway, I have this sequence and I need to know if there is any way to remove the recursion from it:

$\displaystyle {a}_{1} = 1 $

$\displaystyle {a}_{n} = 2 * {a}_{n-1} + 3*n$

I tried to somehow turn it into exponential function but I don't know how, then I thought about moving something to the other side but I don't think it would work either. Is it even possible to write it without recursion?