\begin{equation}
    L_{i+1}(u) = \text{hash}\left(L_i(u), \text{sort}\left(\left(L_i(v_1), \dots, L_i(v_{\vert N(u) \vert})\right)\right)\right), v_j \in N(u), j \in \{1, \dots, \vert N(u) \vert\},
\end{equation}
