activity
20242026
collaborators

16 papers

math.CO2026

Nonhamiltonian regular sublinear expanders

Chengli Li, Yurui Tang

Letzter, Methuku and Sudakov proved that sufficiently regular sublinear expanders contain nearly spanning cycles and paths. Montgomery subsequently conjectured that every regular s…

math.CO2026

Edge-disjoint Hamilton cycles under a bipartite-hole condition

Yanan Hu, Chengli Li, Feng Liu

In 2017, McDiarmid and Yolov introduced the bipartite-hole-number and proved that forces a Hamilton cycle. They also gave a sufficient con…

math.CO2026

The number of cycles of a given length in dense hamiltonian graphs: proving Hilton's conjecture

Chengli Li, Leyou Xu, Bo Zhou

A classical theorem of Sheehan in 1977 states that every hamiltonian graph of order satisfying contains at least two cycles…

math.CO2026

The maximum number of paths of a given length in a nonhamiltonian graph

Chengli Li, Xingzhi Zhan

In 1980, Paul Erdős posed the following problem: For every positive integer determine a nonhamiltonian graph of order having the maximum number of Hamilton paths. We solve…

math.CO2025

Every -connected -graph of order at least seven contains a pancyclic edge

Chengli Li, Xingzhi Zhan

A graph is called an -graph if any induced subgraph of of order has size at least An edge in a graph of order is called pancyclic if for every i…

math.CO2025

Cycles of consecutive lengths in -connected graphs

Chengli Li, Xingzhi Zhan

Recently Lin, Wang and Zhou have proved that every -connected nonbipartite graph of minimum degree at least with and order at least contains cycles of con…