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T. Amdeberhan
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Let $F(x,y)=\sum_{n,m\geq0}Q_n^mx^my^m$ be a generating function. Based on the recurrence relation alone, you should be getting $$F(x,y)=\frac{P(x,y)}{1-2y-xy^2};$$ for some polynomial $P(x,y)$ which depends on the initial conditions (this, I leave up to you).

Caveat. You last initial condition does not sync with the recurrence. For example, $Q(3,3)=2Q(3,2)+Q(2,1)=0$ but supposedly $Q(3,3)=1$ and $Q(3,2)=Q(2,1)=0$. A mismatch!

T. Amdeberhan
  • 43.2k
  • 5
  • 57
  • 217