Runrun Liu

collaborators

3 papers

math.CO2026

Flexible DP-4-coloring of planar graphs without 4-cycles and intersecting triangles

Shu Fang, Runrun Liu, Gexin Yu

Graph coloring with preferences offers a powerful framework for constraint satisfaction problems in which fulfilling every request is impossible but satisfying a guaranteed positiv…

math.CO2025

List-recoloring of two classes of planar graphs

Chenran Pan, Weifan Wang, Runrun Liu

For a graph $G$ with a list assignment $L$ and two $L$ -colorings $I^\pm$ and $I^^{2}$ , an $L$ -recoloring sequence from $I^\pm$ to $I^^{2}$ is a sequence of proper $L$ -colorings where consecutive…

math.CO2025

Connectivity of contraction-critical graphs

Michael Lafferty, Runrun Liu, Martin Rolek +1

Contraction-critical graphs came from the study of minimal counterexamples to Hadwiger's conjecture. A graph is $k$ -contraction-critical if it is $k$ -chromatic, but any proper mino…