Chunlei Zu

activity

20212025

collaborators

3 papers

math.CO2025

On the number of triangles in $K_{4}$ -free graphs

Jialin He, Jie Ma, Yan Wang +1

Erdős asked whether for any $n$ -vertex graph $G$ , the parameter $p^{*} (G) = min \sum_{i \geq 1} (∣ V (G_{i}) ∣ - 1)$ is at most $⌊ n^{2} /4 ⌋$ , where the minimum is taken over all edge…

math.CO2023

Optimal bisections of directed graphs

Guanwu Liu, Jie Ma, Chunlei Zu

In this paper, motivated by a problem of Scott and a conjecture of Lee, Loh and Sudakov we consider bisections of directed graphs. We prove that every directed graph with $m$ arcs…

math.CO2021

Towards a conjecture of Birmelé-Bondy-Reed on the Erdős-Pósa property of long cycles

Jie Ma, Chunlei Zu

A conjecture of Birmelé, Bondy and Reed states that for any integer $ℓ \geq 3$ , every graph $G$ without two vertex-disjoint cycles of length at least $ℓ$ contains a set of at…

On the number of triangles in K4​-free graphs

Optimal bisections of directed graphs

Towards a conjecture of Birmelé-Bondy-Reed on the Erdős-Pósa property of long cycles

On the number of triangles in $K_{4}$ -free graphs