A 6-chromatic two-distance graph in the plane

2019/09/29 by Geoffrey Exoo, Exoo, Geoffrey, Dan Ismailescu +1
Computer Science · Engineering · #Combinatorics (math.CO) #FOS: Mathematics #Graph Labeling and Dimension Problems #graph theory and CDMA systems

paper · pdf · doi:10.48550/arxiv.1909.13177

openalex publication_date 2019/09/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We prove that if one colors each point of the Euclidean plane with one of five colors, then there exist two points of the same color that are either distance 1 or distance 2 apart.

Citations

• Computing Small Unit-Distance Graphs with Chromatic Number 5

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