\begin{align*}
&g\left(0\right)+\\
&f\left(\{0\},\{1\}\right)g\left(1\right)+\\
&f\left(\{0,1\},\{2,3\}\right)\Big[g\left(2\right)+f\left(\{2\},\{3\}\right)g\left(3\right)\Big]+\\&f\left(\{0,1,2,3\},\{4,5,6,7\}\right)\bigg[g\left(4\right)+f\left(\{4\},\{5\}\right)g\left(5\right)+f\left(\{4,5\},\{6,7\}\right)\left[g\left(6\right)+f\left(\{6\},\{7\}\right)g\left(7\right)\right]\bigg]
\end{align*}