Given that the following sequence, Q_{n} , satisfies a homogeneous second order difference equation with constant coefficients find Q_{n} :

$\displaystyle Q_{1} = 1, Q_{2} = 3, Q_{3} = 4, Q_{4} = 7, Q_{5} = 11, Q_{6} = 18, ... $

I reckon that it would have to start with $\displaystyle AQ_{n} + BQ_{n - 1} + CQ_{n - 2} = 0 $ and do i then just put in the various numbers and solve them simultaneiously?