Contact graphs of ball packings
arXiv:1707.02526 · doi:10.1016/j.jctb.2020.05.007
Abstract
A contact graph of a packing of closed balls is a graph with balls as vertices and pairs of tangent balls as edges. We prove that the average degree of the contact graph of a packing of balls (with possibly different radii) in is not greater than . We also find new upper bounds for the average degree of contact graphs in and .