A special case of Vu's conjecture: Coloring nearly disjoint graphs of bounded maximum degree

09/23/2021
by   Tom Kelly, et al.
0

A collection of graphs is nearly disjoint if every pair of them intersects in at most one vertex. We prove that if G_1, …, G_m are nearly disjoint graphs of maximum degree at most D, then the following holds. For every fixed C, if each vertex v ∈⋃_i=1^m V(G_i) is contained in at most C of the graphs G_1, …, G_m, then the (list) chromatic number of ⋃_i=1^m G_i is at most D + o(D). This result confirms a special case of a conjecture of Vu and generalizes Kahn's bound on the list chromatic index of linear uniform hypergraphs of bounded maximum degree. In fact, this result holds for the correspondence (or DP) chromatic number and thus implies a recent result of Molloy, and we derive this result from a more general list coloring result in the setting of `color degrees' that also implies a result of Reed and Sudakov.

READ FULL TEXT

page 1

page 2

page 3

page 4

research
05/04/2021

2-distance list (Δ+ 3)-coloring of sparse graphs

A 2-distance list k-coloring of a graph is a proper coloring of the vert...
research
10/15/2018

Colouring Graphs with Sparse Neighbourhoods: Bounds and Applications

Let G be a graph with chromatic number χ, maximum degree Δ and clique nu...
research
11/06/2019

A local epsilon version of Reed's Conjecture

In 1998, Reed conjectured that every graph G satisfies χ(G) ≤1/2(Δ(G) + ...
research
07/12/2021

Coloring graphs with forbidden bipartite subgraphs

A conjecture of Alon, Krivelevich, and Sudakov states that, for any grap...
research
06/02/2022

Min orderings and list homomorphism dichotomies for signed and unsigned graphs

The CSP dichotomy conjecture has been recently established, but a number...
research
04/17/2022

Optimally Reconfiguring List and Correspondence Colourings

The reconfiguration graph 𝒞_k(G) for the k-colourings of a graph G has a...
research
06/10/2023

List homomorphisms to separable signed graphs

The complexity of the list homomorphism problem for signed graphs appear...

Please sign up or login with your details

Forgot password? Click here to reset