Brouwer–Haemers graph
| Brouwer–Haemers graph | |
|---|---|
 | |
| Vertices | 81 |
| Edges | 810 |
| Girth | 3 |
| Automorphisms | 233,280 |
| Chromatic number | 7 |
| Properties | Strongly regular |
In the mathematical field of graph theory, the Brouwer–Haemers graph is a 20-regular undirected graph with 81 vertices and 810 edges. It is the unique strongly regular graph with parameters (81, 20, 1, 6).