This note relates to bounds on the chromatic number χ(ℝn) of the Euclidean space, which is the minimum number of colors needed to color all the points in ℝn so that any two points at the distance 1 receive different colors. In [6] a sequence of graphs Gn in ℝn was introduced showing that . For many years, this bound has been remaining the best known bound for the chromatic numbers of some lowdimensional spaces. Here we prove that and find an exact formula for the chromatic number in the case of n = 2k and n = 2k − 1.
@article{bwmeta1.element.doi-10_7151_dmgt_1641,
author = {J\'ozsef Balogh and Alexandr Kostochka and Andrei Raigorodskii},
title = {Coloring Some Finite Sets in $\mathbb{R}$n},
journal = {Discussiones Mathematicae Graph Theory},
volume = {33},
year = {2013},
pages = {25-31},
zbl = {1296.05066},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_7151_dmgt_1641}
}
József Balogh; Alexandr Kostochka; Andrei Raigorodskii. Coloring Some Finite Sets in ℝn. Discussiones Mathematicae Graph Theory, Tome 33 (2013) pp. 25-31. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_7151_dmgt_1641/
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