collaborators

7 papers

math.CO2026

Inversion diameter and treewidth

Yichen Wang, Haozhe Wang, Yuxuan Yang +1

In an oriented graph , the inversion of a subset of vertices is the operation that reverses the orientation of all arcs with both end-vertices in . The i…

math.CO2026

A generalization of Erdős-Hajnal problem on paths with equal-degree endpoints

Xiamiao Zhao, Yichen Wang, Mei Lu

Erdős and Hajnal proposed a problem that: is it true that every -vertex graph with edges contains two vertices of equal degree connected by a path of length thre…

math.CO2025

Linear recoloring diameter of degenerate chordal graphs and bounded treewidth graphs

Yichen Wang, Mei Lu

Let be a graph on vertices and an integer. The reconfiguration graph of , denoted by , consists of all -colorings of and two -colorings are adjacen…

math.CO2025

Edge version of the inducibility via the entropy method

Yichen Wang, Xiamiao Zhao, Mei Lu

The inducibility of a graph is about the maximum number of induced copies of in a graph on vertices. We consider its edge version, that is, the maximum number of induce…

math.CO2025

The maximum sum of sizes of non-empty cross -intersecting families

Xiamiao Zhao, Haixiang Zhang, Mei Lu

Let , , and be positive integers such that , a non-empty subset of , and for . We say that…

math.CO2025

Treewidth of generalized Hamming graph, bipartite Kneser graph and generalized Petersen graph

Yichen Wang, Mengyu Cao, Zequn Lv +1

Let and be positive integers. Write . The generalized Hamming graph is the graph whose vertex set is the cartesian product of copie…