# The Four-Colour Theorem

@article{Robertson1997TheFT, title={The Four-Colour Theorem}, author={Neil Robertson and Daniel P. Sanders and Paul D. Seymour and Robin Thomas}, journal={J. Comb. Theory, Ser. B}, year={1997}, volume={70}, pages={2-44} }

The four-colour theorem, that every loopless planar graph admits a vertex-colouring with at most four different colours, was proved in 1976 by Appel and Haken, using a computer. Here we give another proof, still using a computer, but simpler than Appel and Haken's in several respects.

## 599 Citations

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- 1996

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