An Implicit Degree Dirac Condition for Hamiltonian Cycles

Huawei Dai1, Junqing Cai2
1Department of Mathematics, Huizhou University, Huizhou 516007, P.R. China
2School of Management, Qufu Norma! University, Rizhao, 276826, P.R. China

Abstract

In \(1989\), Zhu, Li, and Deng introduced the definition of implicit degree, denoted by \(\text{id}(v)\), of a vertex \(v\) in a graph \(G\) and they obtained sufficient conditions for a graph to be hamiltonian with the implicit degrees. In this paper, we prove that if \(G\) is a \(2\)-connected graph of order \(n\) with \(\alpha(G) \leq n/2\) such that \(\text{id}(v) \geq (n-1)/2\) for each vertex \(v\) of \(G\), then \(G\) is hamiltonian with some exceptions.