Monatshefte für Mathematik

, Volume 79, Issue 3, pp 201–211

Gedanken zur Vier-Farben-Vermutung

  • Authors
  • Herbert Fleischner

DOI: 10.1007/BF01304073

Cite this article as:
Fleischner, H. Monatshefte für Mathematik (1975) 79: 201. doi:10.1007/BF01304073

Some thoughts on the four colour conjecture


It is shown that the four colour conjecture is equivalent to a conjecture on the existence of spanning Eulerian subgraphs of a certain type in triangulations of the plane. From this, a simple proof of Heawood's Equivalence Theorem is given. Moreover, an elementary operation is defined for triangulations of the plane; and by repeated application of this operation one can construct a given colouring from another given colouring.

Copyright information

© Springer-Verlag 1975