Another six-coloring of the plane
β Scribed by Ilya Hoffman; Alexander Soifer
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 92 KB
- Volume
- 150
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
A six-coloring of the Euclidean plane is constructed such that the distance 1 is not realized by any color except one, which does not realize the distance x/2 -1.
A 44-year-old problem due to Edward Nelson asks to find the chromatic number x(E 2) of the plane, i.e. the minimal number of colors that are required for coloring the plane so that no two points, a unit distance apart, lie on the same color. (For a history of the problem we refer the reader to .)
It has been known, since 1950, that 4 ~< z(E 2) ~< 7.
π SIMILAR VOLUMES
It was shown (Kronk and Mitchen, 1973) that the set of vertices, edges and faces of any normal map on the sphere can be colored with seven colors. In this paper we solve a somewhat different problem: the set of edges and faces of any plane graph with A ~< 3 can be colored by six colors.
It is shown that the points of a projective plane may be two-&ore discrepancy at most Knf, K an absolute constant. A variant of the p hat evee line has method is used. Connections to the Komlos Conjecture are discussed.
Borodin, O.V., Cyclic coloring of plane graphs, Discrete Mathematics 100 (1992) 281-289. Let G be a plane graph, and let x,(G) be the minimum number of colors to color the vertices of G so that every two of them which lie in the boundary of the same face of the size at most k, receive different colo
## Abstract The vertices of each plane triangulation without loops and multiple edges may be colored with 11 colors so that for every two adjacent triangles [__xyz__] and [__wxy__], the vertices __x__,__y__,__w__,__z__ are colored pairwise differently.
A sequence r 1 , r 2 , . . . , r 2n such that r i = r n+i for all 1 β€ i β€ n is called a repetition. A sequence S is called non-repetitive if no block (i.e. subsequence of consecutive terms of S) is a repetition. Let G be a graph whose edges are colored. A trail is called non-repetitive if the sequen