Ligong Wang

activity

20152023

most citedOrdering of bicyclic graphs by matching energy

7 citations · 33 across the 43 of their papers we have counts for

collaborators

Showing 2016Show all

11 papers · 1 filter

math.CO2016★ 1 cited

Skew-rank of an oriented graph in terms of the rank and dimension of cycle space of its underlying graph

Yong Lu, Ligong Wang, Qiannan Zhou

Let $G^{σ}$ be an oriented graph and $S (G^{σ})$ be its skew-adjacency matrix, where $G$ is called the underlying graph of $G^{σ}$ . The skew-rank of $G^{σ}$ , denoted by $sr (G^{σ})$ , is the ra…

math.CO2016

On the signless Laplacian spectral radius of $C_{4}$ -free $k$ -cyclic graphs

Qi Kong, Ligong Wang

A $k$ -cyclic graph is a connected graph of order $n$ and size $n + k - 1$ . In this paper, we determine the maximal signless Laplacian spectral radius and the corresponding extremal gra…

math.CO2016

Upper bounds on the Q-spectral radius of book-free and/or $K_{s, t}$ -free graphs

Qi Kong, Ligong Wang

In this paper, we prove two results about the signless Laplacian spectral radius $q (G)$ of a graph $G$ of order $n$ with maximum degree $Δ$ . Let $B_{n} = K_{2} + K_{n}$ deno…

math.CO2016

Hermitian-Randić matrix and Hermitian-Randić energy of mixed graphs

Yong Lu, Ligong Wang, Qiannan Zhou

Let $M$ be a mixed graph and $H (M)$ be its Hermitian-adjacency matrix. If we add every edge and arc in $M$ a Randić weight, then we can get a new weighted Hermitian-adjacency matri…

math.CO2016

The signless Laplacian spectral radius of subgraphs of regular graphs

Qi Kong, Ligong Wang

Let $q (H)$ be the signless Laplacian spectral radius of a graph $H$ . In this paper, we prove that \\1. Let $H$ be a proper subgraph of a $Δ$ -regular graph $G$ with $n$ vertices and…

math.CO2016

Some upper bounds for the signless Laplacian spectral radius of digraphs

Weige Xi, Ligong Wang

Let $G = (V (G), E (G))$ be a digraph without loops and multiarcs, where $V (G) = {v_{1}, v_{2}, \dots, v_{n}}$ and $E (G)$ are the vertex set and the arc set of $G$ , respectively. Let $d_{i}^{+}$ …

math.CO2016

Distance signless Laplacian spectral radius and Hamiltonian properties of graphs

Qiannan Zhou, Ligong Wang

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 L…

math.CO2016

Minimal Skew energy of oriented bicyclic graphs with a given diameter

Xiangxiang Liu, Ligong Wang

Let $S (G^{σ})$ be the skew-adjacency matrix of the oriented graph $G^{σ}$ , which is obtained from a simple undirected graph $G$ by assigning an orientation $σ$ to each of its edges. Th…

math.CO2016

On the second smallest and the largest normalized Laplacian eigenvalues of a graph

Xiaoguo Tian, Ligong Wang, Yong Lu

Let $G$ be a simple connected graph with order $n$ . Let $L (G)$ be the normalized Laplacian matrix of $G$ . Let $λ_{k} (G)$ be the $k$ -th smallest normalized Laplacian eigen…

math.CO2016

5-regular oriented graphs with optimum skew energy

Lifeng Guo, Ligong Wang, Peng Xiao

Let $G$ be a simple undirected graph and $G^{σ}$ be the corresponding oriented graph of $G$ with the orientation $σ$ . The skew energy of $G^{σ}$ , denoted by $ε_{s} (G^{σ})$ , is de…

math.CO2016★ 4 cited

A new S-type eigenvalue localization set for tensors and its applications

Zhengge Huang, Ligong Wang, Zhong Xu +1

A new \emph{S}-type eigenvalue localization set for tensors is derived by breaking $N = {1, 2, \dots, n}$ into disjoint subsets $S$ and its complement. It is proved that this new set…

Skew-rank of an oriented graph in terms of the rank and dimension of cycle space of its underlying graph

On the signless Laplacian spectral radius of C4​-free k-cyclic graphs

Upper bounds on the Q-spectral radius of book-free and/or Ks,t​-free graphs

Hermitian-Randić matrix and Hermitian-Randić energy of mixed graphs

The signless Laplacian spectral radius of subgraphs of regular graphs

Some upper bounds for the signless Laplacian spectral radius of digraphs

Distance signless Laplacian spectral radius and Hamiltonian properties of graphs

Minimal Skew energy of oriented bicyclic graphs with a given diameter

On the second smallest and the largest normalized Laplacian eigenvalues of a graph

5-regular oriented graphs with optimum skew energy

A new S-type eigenvalue localization set for tensors and its applications

On the signless Laplacian spectral radius of $C_{4}$ -free $k$ -cyclic graphs

Upper bounds on the Q-spectral radius of book-free and/or $K_{s, t}$ -free graphs