collaborators

7 papers

math.CO2026

The strong fractional choice number of triangle-free planar graphs

Xiaolan Hu, Rongxing Xu

Let be positive integers with . A graph is -choosable if, for every assignment of lists of size to the vertices of , there exists a choice of…

math.CO2026

Degree-choosability of proper conflict-free list coloring of sparse graphs

Masaki Kashima, Riste Å krekovski, Rongxing Xu

Given a graph and a mapping , an -list assignment of is a function that maps each to a set of at least colors. For an -list…

math.CO2025

Partitioning triangle-free planar graphs into a forest and a linear forest

Guanwu Liu, Rongxing Xu

Raspaud and Wang conjectured that every triangle-free planar graph can be vertex-partitioned into an independent set and a forest. Independently, Kawarabayashi and Thomassen also r…

math.CO2025

Remarks on proper conflict-free degree-choosability of graphs with prescribed degeneracy

Masaki Kashima, Riste Å krekovski, Rongxing Xu

A proper coloring of is called a proper conflict-free coloring of if for every non-isolated vertex of , there is a color such that $|ϕ^{-1}(c)\cap N_G(v)|=…

math.CO2025

Proof of a conjecture of Voss on bridges of longest cycles

Jie Ma, Rongxing Xu

Bridges are a classical concept in structural graph theory and play a fundamental role in the study of cycles. A conjecture of Voss from 1991 asserts that if disjoint bridges $B_1,…

math.CO2025

Proper conflict-free degree-choosability of outerplanar graphs

Masaki Kashima, Riste Å krekovski, Rongxing Xu

A proper coloring of is called a proper conflict-free coloring of if for every non-isolated vertex of , there is a color such that $|ϕ^{-1}(c)\cap N_G(v)|=…