中文
相关论文

相关论文: Signless Laplacian spectral radius and Hamiltonici…

200 篇论文

In this paper, we present a spectral sufficient condition for a graph to be Hamilton-connected in terms of signless Laplacian spectral radius with large minimum degree.

组合数学 · 数学 2017-12-01 Qiannan Zhou , Ligong Wang , Yong Lu

In this paper, we study the Hamiltonicity of graphs with large minimum degree. Firstly, we present some conditions for a simple graph to be Hamilton-connected and traceable from every vertex in terms of the spectral radius of the graph or…

组合数学 · 数学 2017-11-29 Guidong Yu , Yi Fang , Yizheng Fan , Gaixiang Cai

In this paper, first, we establish a sufficient condition for a bipartite graph to be Hamilton-connected. Furthermore, we also give two sufficient conditions on distance signless Laplacian spectral radius for a graph to be…

组合数学 · 数学 2016-10-25 Qiannan Zhou , Ligong Wang

In this paper, we present some spectral sufficient conditions for a graph to be Hamilton-connected in terms of the spectral radius or signless Laplacian spectral radius of the graph. Our results improve some previous work.

组合数学 · 数学 2017-11-09 Qiannan Zhou , Ligong Wang , Yong Lu

In this paper, we determine the maximal Laplacian and signless Laplacian spectral radii for graphs with fixed number of vertices and domination number, and characterize the extremal graphs respectively.

组合数学 · 数学 2013-10-29 Rundan Xing , Bo Zhou

In this paper, we give sufficient conditions on the spectral radius for a bipartite graph to Hamiltonian and traceable, which expand the results of Lu, Liu and Tian (2012) [10]. Furthermore, we also present tight sufficient conditions on…

组合数学 · 数学 2015-07-07 Ruifang Liu , Wai Chee Shiu , Jie Xue

In this paper, we present a sharp upper and lower bounds for the signless Laplacian spectral radius of graphs in terms of clique number. Moreover, the extremal graphs which attain the upper and lower bounds are characterized. In addition,…

组合数学 · 数学 2012-09-17 Bian He , Ya-Lei Jin , Xiao-Dong Zhang

In this paper we establish some spectral conditions for a graph to be Hamilton-connected in terms of the spectral radius of the adjacency matrix or the signless Laplacian of the graph or its complement. For the existence of Hamiltonian…

组合数学 · 数学 2014-09-19 Gui-Dong Yu , Yi-Zheng Fan

This survey is two-fold. We first report new progress on the spectral extremal results on the Tur\'{a}n type problems in graph theory. More precisely, we shall summarize the spectral Tur\'{a}n function in terms of the adjacency spectral…

组合数学 · 数学 2022-05-13 Yongtao Li , Weijun Liu , Lihua Feng

We obtain new bounds for the Laplacian spectral radius of a signed graph. Most of these new bounds have a dependence on edge sign, unlike previously known bounds, which only depend on the underlying structure of the graph. We then use some…

组合数学 · 数学 2011-03-25 Nathan Reff

Let $G=(V(G),E(G))$ be a simple graph, where $V(G)$ and $E(G)$ are the vertex set and the edge set of $G$, respectively. The number of components of $G$ is denoted by $c(G)$. Let $t$ be a positive real number, and a connected graph $G$ is…

组合数学 · 数学 2025-04-14 Xiangge Liu , Yong Lu , Caili Jia , Qiannan Zhou , Yue Cui

In this paper we determine the graph whose least eigenvalue of signless Laplacian attains the minimum or maximum among all connected non-bipartite graphs of fixed order and given number of pendant vertices. Thus we obtain a lower bound and…

组合数学 · 数学 2014-09-19 Yi-Zheng Fan , Yi Wang , Huan Guo

Let G be a graph and let \Delta,\delta be the maximum and minimum degrees of G respectively, where \Delta/\delta<c<\sqrt{2} and c is a constant. In this paper we establish a sufficient spectral condition for the graph G to be Hamiltonian,…

组合数学 · 数学 2012-07-31 Yi-Zheng Fan , Gui-Dong Yu

Tur\'{a}n type extremal problem is how to maximize the number of edges over all graphs which do not contain fixed forbidden subgraphs. Similarly, spectral Tur\'{a}n type extremal problem is how to maximize (signless Laplacian) spectral…

组合数学 · 数学 2020-07-20 Ming-Zhu Chen , A-Ming Liu , Xiao-Dong Zhang

M. Aouchiche and P. Hansen proposed the distance Laplacian and the distance signless Laplacian of a connected graph [Two Laplacians for the distance matrix of a graph, LAA 439 (2013) 21{33]. In this paper, we obtain three theorems on the…

组合数学 · 数学 2013-08-16 Wenxi Hong , Lihua You

A graph $G$ is $k$-factor-critical if $G-S$ has a perfect matching for any $k$-subset $S$ of the vertex set of $G$. In this paper, we investigate the factor-criticality of graphs with fixed minimum degree and provide sufficient conditions…

组合数学 · 数学 2024-01-03 Jin Cai , Bo Zhou

A graph $G$ is $k$-edge-Hamiltonian if any collection of vertex-disjoint paths with at most $k$ edges altogether belong to a Hamiltonian cycle in $G$. A graph $G$ is $k$-Hamiltonian if for all $S\subseteq V(G)$ with $|S|\le k$, the subgraph…

组合数学 · 数学 2024-04-09 Yongtao Li , Yuejian Peng

Let $F_{a_1,\dots,a_k}$ be a graph consisting of $k$ cycles of odd length $2a_1+1,\dots, 2a_k+1$, respectively which intersect in exactly a common vertex, where $k\geq1$ and $a_1\ge a_2\ge \cdots\ge a_k\ge 1$. In this paper, we present a…

组合数学 · 数学 2021-08-10 Ming-Zhu Chen , A-Ming Liu , Xiao-Dong Zhang

Let $k$ and $n$ be two nonnegative integers with $n\equiv0$ (mod 2), and let $G$ be a graph of order $n$ with a 1-factor. Then $G$ is said to be $k$-extendable for $0\leq k\leq\frac{n-2}{2}$ if every matching in $G$ of size $k$ can be…

组合数学 · 数学 2023-03-30 Sizhong Zhou , Yuli Zhang

In this paper we define signless Laplacian matrix of a hypergraph and obtain structural properties from its eigenvalues. We generalize several known results for graphs, relating the spectrum of this matrix with structural parameters of the…

谱理论 · 数学 2024-08-12 Kauê Cardoso , Vilmar Trevisan
‹ 上一页 1 2 3 10 下一页 ›