Walk-matrix

Walk-matrix --- матрица маршрутов.

The walk-matrix of a graph [math]\displaystyle{ G }[/math] is defined by [math]\displaystyle{ W(G) = (w_{ij}) }[/math], where [math]\displaystyle{ w_{ij} }[/math] is the number of walks in [math]\displaystyle{ G }[/math] of length [math]\displaystyle{ j }[/math] that start at [math]\displaystyle{ v_{i} }[/math], [math]\displaystyle{ 1 \leq i \leq n }[/math], [math]\displaystyle{ 1 \leq j \leq n-1 }[/math].