6 papers · 1 filter
The signless Laplacian spectral Turán problems for disjoint triangles
Ming-Zhu Chen, Ya-Lei Jin, Peng-Li Zhang
The classical Turán-type problem for graphs forbidding disjoint triangles has been resolved firstly by Erdős [Arch. Math. 13 (1962) 222-227] for graphs of sufficiently large or…
A solution to a conjecture on the signless Laplacian spectral radius for -color-critical graphs
Ming-Zhu Chen, Ya-Lei Jin, Peng-Li Zhang +1
An induced matching is a matching that forms an induced subgraph. A graph is -color-critical if removing some induced matching of size lowers its chromatic number, but remov…
Turán extremal graphs vs. Signless Laplacian spectral Turán extremal graphs
Ming-Zhu Chen, Ya-Lei Jin, Peng-Li Zhang +1
Let be a graph with chromatic number . Denote by and the Turán number and the set of all extremal graphs for , respectively. In addition, $…
Some properties of generalized Cayley graphs
Liao Qianfen, Liu Weijun, Zhang Pengli
In this paper, firstly, we provide some necessary and sufficient conditions for generalized Cayley graphs on abelian groups to be bipartite. Secondly, we deduce several necessary a…
The Q-index and connectivity of graphs
Peng-Li Zhang, Lihua Feng, Weijun Liu +1
A connected graph is said to be -connected if it has more than vertices and remains connected whenever fewer than vertices are deleted. In this paper, for a connecte…
Lower bounds for the -spectral radius of uniform hypergraphs
Peng-Li Zhang, Xiao-Dong Zhang
For , the -spectral radius of a -uniform hypergraph is defined to be the spectral radius of the tensor $\mathcal{A}_α(G):=α\mathcal{D}(G)+(1-α) \m…