English

Cayley properties of the line graphs induced by consecutive layers of the hypercube

Group Theory 2019-04-26 v4

Abstract

Let n>3n >3 and 0<k<n2 0< k < \frac{n}{2} be integers. In this paper, we investigate some algebraic properties of the line graph of the graph Qn(k,k+1) {Q_n}(k,k+1) where Qn(k,k+1) {Q_n}(k,k+1) is the subgraph of the hypercube QnQ_n which is induced by the set of vertices of weights kk and k+1k+1. In the first step, we determine the automorphism groups of these graphs for all values of n,kn,k. In the second step, we study Cayley properties of the line graphs of these graphs. In particular, we show that if k3k\geq 3 and n2k+1 n \neq 2k+1, then except for the cases k=3,n=9k=3, n=9 and k=3,n=33k=3, n=33, the line graph of the graph Qn(k,k+1) {Q_n}(k,k+1) is a vertex-transitive non-Cayley graph. Also, we show that the line graph of the graph Qn(1,2) {Q_n}(1,2) is a Cayley graph if and only if n n is a power of a prime pp. Moreover, we show that for \lq{}almost all\rq{} even values of kk, the line graph of the graph Q2k+1(k,k+1) {Q_{2k+1}}(k,k+1) is a vertex-transitive non-Cayley graph.

Keywords

Cite

@article{arxiv.1711.02701,
  title  = {Cayley properties of the line graphs induced by consecutive layers of the hypercube},
  author = {S. Morteza Mirafzal},
  journal= {arXiv preprint arXiv:1711.02701},
  year   = {2019}
}