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.
This graph theory-related article is a stub.