✦ LIBER ✦

A seven-color theorem on the sphere

✍ Scribed by Hudson V. Kronk; John Mitchem

Publisher: Elsevier Science
Year: 1973
Tongue: English
Weight: 731 KB
Volume: 5
Category: Article
ISSN: 0012-365X
DOI: 10.1016/0012-365x(73)90142-8

No coin nor oath required. For personal study only.

✦ Synopsis

Ringel has shown that the set of vertices and regions of any norm:4 map on the sphere can be admissibly colored by six colors. In this paper, it is shown that the set of vertices, edges and regions of any normd map on the sphere tit? be admissibly colored with seven colors.

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