Kittell graph

Kittel graph
The Kittell graph
Vertices 23
Edges 63
Radius 3
Diameter 4
Girth 3
Table of graphs and parameters

In the mathematical field of graph theory, the Kittell graph is a planar graph with 23 vertices and 63 edges. Its unique planar embedding has 42 triangular faces.[1] The Kittell graph is named after Irving Kittell, who used it as a counterexample to Alfred Kempe's flawed proof of the four-color theorem.[2] Simpler counterexamples include the Errera graph and Poussin graph (both published earlier than Kittell) and the Fritsch graph and Soifer graph.

References

  1. Weisstein, Eric W. "Kittell Graph". MathWorld.
  2. Kittell, Irving (1935), "A group of operations on a partially colored map", Bulletin of the American Mathematical Society, 41 (6): 407–413, doi:10.1090/S0002-9904-1935-06104-X, MR 1563103
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.