English

Square coloring planar graphs with automatic discharging

Combinatorics 2022-04-13 v1 Discrete Mathematics

Abstract

The discharging method is a powerful proof technique, especially for graph coloring problems. Its major downside is that it often requires lengthy case analyses, which are sometimes given to a computer for verification. However, it is much less common to use a computer to actively look for a discharging proof. In this paper, we use a Linear Programming approach to automatically look for a discharging proof. While our system is not entirely autonomous, we manage to make some progress towards Wegner's conjecture for distance-22 coloring of planar graphs, by showing that 1212 colors are sufficient to color at distance 22 every planar graph with maximum degree 44.

Keywords

Cite

@article{arxiv.2204.05791,
  title  = {Square coloring planar graphs with automatic discharging},
  author = {Nicolas Bousquet and Lucas de Meyer and Quentin Deschamps and Théo Pierron},
  journal= {arXiv preprint arXiv:2204.05791},
  year   = {2022}
}
R2 v1 2026-06-24T10:45:50.757Z