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The four color theorem has been proved

Publisher: John Wiley and Sons
Year: 1977
Tongue: English
Weight: 26 KB
Volume: 1
Category: Article
ISSN: 0364-9024
DOI: 10.1002/jgt.3190010302

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✦ Synopsis

On the 21st of June 1976, which was the 48th birthday of Wolfgang Haken, he and Kenneth Appel (with the aid of John Koch) completed their proof of the Four Color Theorem. In recognition of their momentous achievement, the Journal ofGruph Theory presents two articles (by Haken and by Frank Bernhart) on this famous problem, preceded by a short poem by the mysterious Blanche Descartes.

The foremost currently unsolved problem in graph theory is, in our considered opinion, the Reconstruction Conjecture.

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