5 papers · 1 filter
Maximizing the signless Laplacian spectral radius of some theta graphs
Yuxiang Liu, Ligong Wang
Let be the signless Laplacian matrix of a simple graph , where and are the degree diagonal matrix and the adjacency matrix of , respectively. T…
Extension on spectral extrema of gem-free graph with given size
Yuxiang Liu, Ligong Wang
A graph is -free if does not contain as a subgraph. Let denote the family of -free graphs with edges and without isolated vertices. Let $S…
Maxima of the -index of 2 leaves-free graphs with given size
Yuxiang Liu, Ligong Wang, Xiaolong Jia
The -index of graph is the largest eigenvalue of the signless Laplacian matrix of . Wang [Discrete Appl. Math. 356(2024)] proved the sharp upper bounds on the -index o…
On the spectral radius of non-transmission regular graphs
Zengzhao Xu, Weige Xi, Ligong Wang
Let be a connected graph with order and size . Let and be the distance matrix and diagonal matrix with vertex transmissions of , respectively. For any…
Matching, odd -factor and distance spectral radius of graphs with given some parameters
Zengzhao Xu, Weige Xi, Ligong Wang
For a connected graph , let denote the distance spectral radius of . A matching in a graph is a set of disjoint edges of . The maximum size of a matching in …