activity
20242026
collaborators

6 papers

math.CO2026

On minimal nonperfectly divisible fork-free graphs

Baogang Xu, Miaoxia Zhuang

A fork is a graph obtained from (usually called claw) by subdividing an edge once. A graph is perfectly divisible if for each of its induced subgraph , can be p…

math.CO2025

Structure and linear-Pollyanna for some square-free graphs

Ran Chen, Baogang Xu

We use and to denote a path and a cycle on vertices, respectively. A {\em bull} is a graph consisting of a triangle with two disjoint pendant edges, a {\em hammer}…

math.CO2025

The optimal binding function for (cap, even hole)-free graphs

Ran Chen, Baogang Xu, Yian Xu

A {\em hole} is an induced cycle of length at least 4, an {\em even hole} is a hole of even length, and a {\em cap} is a graph obtained from a hole by adding an additional vertex w…

math.CO2025

Perfect divisibility of (fork, antifork)-free graphs

Ran Chen, Baogang Xu, Miaoxia Zhuang

A {\em fork} is a graph obtained from (usually called {\em claw}) by subdividing an edge once, an {\em antifork} is the complement graph of a fork, and a {\em co-cricket}…

math.CO2025

Coloring of graphs without long odd holes

Ran Chen, Baogang Xu

A {\em hole} is an induced cycle of length at least 4, a -hole is a hole of length , and an {\em odd hole} is a hole of odd length. Let be an integer. Let ${\cal…

math.CO2024

Nearly optimal coloring of some C4-free graphs

Ran Chen, Baogang Xu

A class of graphs is -{\em polydet} if has a polynomial binding function and there is a polynomial time algorithm to determine an -coloring…