It is proved that the choice number of every graph G embedded on a surface of Euler genus ε ≥ 1 and ε = 3 is at most the Heawood number H(ε) = (7 + √ 24ε + 1)/2 and that the equality holds if and only if G contains the complete graph K H(ε) as a subgraph.
The combinatorial map color theorem
✍ Scribed by Gerhard Ringel
- Publisher
- John Wiley and Sons
- Year
- 1977
- Tongue
- English
- Weight
- 522 KB
- Volume
- 1
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
This paper is written in the spirit of the author's book: Map Color Theorem (1974). We try to develop the Map Color Theorem in a combinatorial way, circumventing the unwieldy embedding theory. Similar (but not identical) generalizations have recently and independently been developed by Alpert (in press) and by Stahl (in press). The first nine theorems are one‐dimensional versions of known facts from the theory of two‐dimensional compact manifolds. Theorems 10 to 13 are to my knowledge completely new results.
📜 SIMILAR VOLUMES
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