Homogeneous Traceability In Claw-Free Graphs

Abstract

A graph \(G\) is homogeneously traceable if for each vertex \(v\) of \(G\) there exists a hamiltonian path in \(G\) with initial vertex \(v\). A graph is called claw-free if it has no induced \(K_3\) as a subgraph.

In this paper, we prove that if \(G\) is a \(k\)-connected (\(k > 1\)) claw-free graph of order \(n\) such that the sum of degrees of any \(k+2\) independent vertices is at least \(n-k\), then \(G\) is homogeneously traceable. For \(k=2\), the bound \(n-k\) is best possible.

As a corollary we obtain that if \(G\) is a \(2\)-connected claw-free graph of order \(n\) such that \(NC(G) \geq (n-3)/2\), where \(NC(G) = \min\{|N(u) \cup N(v)|: uv \notin E(G)\}\), then \(G\) is homogeneously traceable. Moreover, the bound \((n-3)/2\) is best possible.