Distinct trees I

Let $Q(n,m)$ be the number of distinct trees with n nodes where each node can have no more than m edges connected to it. Two trees are not considered distinct if they are isomorphic.

For example, $Q(6,3)=4$. Four distinct trees are shown below.

You are given $Q(15,4)=4347$ and $Q(50,7)\equiv 646618404(\mathrm{mod}1000000007)$

Find $Q(1000,15)mod1000000007$