How to compute the complexity of $T(n) = T(n-2)+T(n-3)+2T(n/3)$?
You can notice that $T(n) &lt; 3T(n-2)$. This gives you the complexity as $O(3^{n/2})$. You can also observe that $T(n) &gt; 2T(n-3)$. This gives you the complexity as $\Omega(2^{n/3})$. Now, you can at least tell that the complexity is an exponential one.