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The chromatic number of the sphere

Published online by Cambridge University Press:  09 April 2009

Gustavus J. Simmons
Affiliation:
Department of Mathematics Sandia Laboratories Albuquerque, New Mexico, 87115, U.S.A.
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Abstract

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Erdös, Harary and Tutte have defined the chromatic number of the plane to be the least number of sets partitioning the plane such that no set contains two points at unit distance apart. By analogy, the chromatic number χ(S1), of the sphere, Sr of radius r is defined to be the least number of sets partitioning the surface of Sr such that no set contains two points at unit chordal distance apart. In this paper it is proven that and that this bound is best possible since .

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1976

References

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