A Characterization of Halved Cubes

Wilfried Imrich1, Sandi Klavzar2, Aleksander Vesel2
1 Department of Mathematics and Applied Geometry Montanuniversitat Leoben A-8700 Leoben, Austria
2Department of Mathematics, PEF University of Maribor Koroska cesta 160 62000 Maribor, Slovenia

Abstract

The vertex set of a halved cube \(Q’_d\) consists of a bipartition vertex set of a cube \(Q_d\) and two vertices are adjacent if they have a common neighbour in the cube. Let \(d \geq 5\). Then it is proved that \(Q’_d\) is the only connected, \(\binom{d}{3}\)-regular graph on \(2^d\) vertices in which every edge lies in two \(d\)-cliques and two \(d\)-cliques do not intersect in a vertex.