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On the chromatic number of binary matroids

Part of: Designs and configurations

Published online by Cambridge University Press:  26 February 2010

P. N. Walton  and
D. J. A. Welsh
P. N. Walton
Affiliation:
Merton College Oxford.
D. J. A. Welsh
Affiliation:
Merton College Oxford.
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Extract

In this paper we obtain matroid extensions of two important results in graph theory, namely the 4-colour theorem of Appel and Haken [1] and the 8-flow theorem of Jaeger [4]. As a corollary we prove that any bridgeless graph with no subgraph contractible to K3,3 has a nowhere zero 4-flow. These results depend heavily on a remarkable theory of splitters developed recently by Seymour [8], [9].

MSC classification

Secondary: 05B35: Matroids, geometric lattices
Type
Research Article
Information
Mathematika , Volume 27 , Issue 1 , June 1980 , pp. 1 - 9
Copyright
Copyright © University College London 1980

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References

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