Herschel graph

Herschel graph
The Herschel graph.
Named after	Alexander Stewart Herschel
Vertices	11
Edges	18
Automorphisms	12 (D6)
Properties	Polyhedral Bipartite non-Hamiltonian
Table of graphs and parameters

In graph theory, a branch of mathematics, the Herschel graph is a bipartite undirected graph with 11 vertices and 18 edges. It is a polyhedral graph (the graph of a convex polyhedron), and is the smallest polyhedral graph that does not have a Hamiltonian cycle, a cycle passing through all its vertices. It is named after British astronomer Alexander Stewart Herschel, because of Herschel's studies of Hamiltonian cycles in polyhedral graphs (but not of this graph).