Hostname: page-component-8448b6f56d-42gr6 Total loading time: 0 Render date: 2024-04-24T14:50:36.308Z Has data issue: false hasContentIssue false

A 4-chromatic graph with a special plane drawing

Published online by Cambridge University Press:  09 April 2009

Nicholas Wormald
Affiliation:
Department of Mathematics University of Newcastle Newcastle, N.S.W. 2308, Australia
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

A graph is found which is 4-chromatic, has girth 5, and can be obtained by taking a set S of points in the plane and joining two of the points whenever their distance is 1. The points in S are not found explicitly, but their existence is demonstrated by use of a computer.

Subject classification (Amer. Math. Soc. (MOS) 1970): 05 C 15, 05 C 10.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1979

References

Hadwiger, H., Debrunner, H. and Klee, V. (1964), Combinatorial geometry in the plane (Holt, Rinehart & Winston, New York).Google Scholar
Harary, F. (1969), Graph theory (Addison-Wesley, Reading, Mass.).CrossRefGoogle Scholar
Moser, L. and Moser, W. (1961), ‘Solution to problem 10’, Canad. Math. Bull. 4, 187189.Google Scholar