I am trying to solve a recursion of the form \begin{equation*}a_n=\sum_{j=1}^{n-1} k_{j,n} \cdot a_j + d_n \end{equation*} where $k_{j,n}$ and $d_n$ are constants depending on $j,n$ and $n$, respectively. Does a closed form to express $a_n$ explicitly exist? Or does anyone have similar examples?
Many Thanks!!