## Abstract It has been shown that every quadrangulation on any nonspherical orientable closed surface with a sufficiently large representativity has chromatic number at most 3. In this paper, we show that a quadrangulation __G__ on a nonorientable closed surface __N~k~__ has chromatic number at le
Realizing the chromatic numbers of triangulations of surfaces
โ Scribed by Frank Harary; Serge Lawrencenko; Vladimir Korzhik
- Publisher
- Elsevier Science
- Year
- 1993
- Tongue
- English
- Weight
- 440 KB
- Volume
- 122
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
โฆ Synopsis
Given an orientable or nonorientable closed surface S and an integer n not less than 3 and not greater than the chromatic number of S, we construct a graph admitting a triangular embedding in S and having chromatic number n.
In general we follow the terminology and notation of [3].
๐ SIMILAR VOLUMES
A graph G is called triangulated (or rigid-circuit graph, or chordal graph) if every circuit of G with length greater than 3 has a chord. It can be shown (see, UI, . . . , u,, . Let G = G,.
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