Strong Connectivity in Directional Nearest-Neighbor Graphs
Bruce E. Flinchbaugh, Lee Kenneth Jones · SIAM Journal on Algebraic and Discrete Methods · 1981
A Directional Nearest-Neighbor graph is defined on a finite set of points in the plane by drawing an arc from each point X to its nearest neighbor in each of r divisions of the plane relative to X. We prove that Directional Nearest-Neighbor graphs having $r = 4$ are strongly connected.