# Simplifying Factorials

How would I go about simplifying something like:
(n+3)!/(n+1)! ?

$$\frac{(n+3)!}{(n+1)!} = \frac{(n+3)(n+2)\cdot(n+1)!}{(n+1)!}=(n+2)(n+3) = n^2 + 5n + 6$$