Kun Cheng

collaborators

3 papers

math.CO2025

Extending two results on hamiltonian graphs involving the bipartite-hole-number

Kun Cheng, Yurui Tang

The bipartite-hole-number of a graph $G$ , denoted by $I^\pm (G)$ , is the minimum number $k$ such that there exist positive integers $s$ and $t$ with $s + t = k + 1$ with the proper…

math.CO2024

Constructions of minimally $t$ -tough regular graphs

Kun Cheng, Chengli Li, Feng Liu

A non-complete graph $G$ is said to be $t$ -tough if for every vertex cut $S$ of $G$ , the ratio of $∣ S ∣$ to the number of components of $G - S$ is at least $t$ . The toughness $I ¨ (G)$ …

math.CO2024

Sparse graphs with an independent or foresty minimum vertex cut

Kun Cheng, Yurui Tang, Xingzhi Zhan

A connected graph is called fragile if it contains an independent vertex cut. In 2002 Chen and Yu proved that every connected graph of order $n$ and size at most $2 n - 4$ is fragile,…

Extending two results on hamiltonian graphs involving the bipartite-hole-number

Constructions of minimally t-tough regular graphs

Sparse graphs with an independent or foresty minimum vertex cut

Constructions of minimally $t$ -tough regular graphs