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A Categorical Characterization of the Four Colour Theorem

Published online by Cambridge University Press:  20 November 2018

Barry Fawcett*
Affiliation:
Dept. of Mathematics Statistics and Computing Science Dalhousie University Halifax, N.S. B3H 3J5
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Abstract

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The surjectivity of epimorphisms in the category of planar graphs and edge-preserving maps follows from and is implied by the Four Colour Theorem. The argument that establishes the equivalence is not combinatorially complex.

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1986

References

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