5 papers
Extremal spectral radius of nonregular graphs with a fixed odd maximum degree
Zejun Huang, Chenxi Yang
For integers and , let be the maximum adjacency spectral radius among all connected nonregular graphs of order and maximum degree . Liu conj…
Three Results on Generalized Quasikernels in Digraphs
Zejun Huang, Chenxi Yang
A -kernel of a digraph is an independent set such that every vertex of is reachable from by a directed path of length at most , which is a natural…
Nonregular graphs with a given maximum degree attaining maximum spectral radius
Zejun Huang, Jiahui Liu, Chenxi Yang
Let be a connected nonregular graphs of order with maximum degree that attains the maximum spectral radius. Liu and Li (2008) proposed a conjecture stating that has…
Extremal digraphs containing at most paths of length 2 with the same endpoints
Zejun Huang, Zhenhua Lyu
Given a positive integer , let be the digraph consisting of directed paths of length 2 with the same initial and terminal vertices. In this paper, we study the max…
Extremal oriented graphs avoiding 1-subdivision of an in-star
Zejun Huang, Chenxi Yang
An oriented graph is a digraph obtained from an undirected graph by choosing an orientation for each edge. Given a positive integer and an oriented graph , the oriented Tur$…