Qiannan Zhou

collaborators

2 papers

math.CO2026

Hamiltonian cycles in 7-tough $(P_{4} \cup P_{1})$ -free graphs

Yong Lu, Qi Wu, Qiannan Zhou

Shan~[J. Graph Theory (2026)] proved that every 23-tough $(P_{4} \cup P_{1})$ -free graph on at least three vertices is Hamiltonian. We improve this bound to 7 by replacing the final cut…

math.CO2025

Distance signless Laplacian spectral radius and tough graphs involving minimun degree

Xiangge Liu, Yong Lu, Caili Jia +2

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 $…

Hamiltonian cycles in 7-tough (P4​∪P1​)-free graphs

Distance signless Laplacian spectral radius and tough graphs involving minimun degree

Hamiltonian cycles in 7-tough $(P_{4} \cup P_{1})$ -free graphs