Exept from the Kn,n graphs there are exactly seven triangle free strongly regular graphs known:
 1. Five cycle: (5,2,0,1) |
 2. Petersen graph: (10,3,0,1) |
 3. Clebsch graph: (16,5,0,2) |
 4. Hoffman-Singleton graph: (50,7,0,1) |
 5. Gewirtz graph: (56,10,0,2) |
 6. Higman-Sims graph: (100,22,0,6) |
7. The M22 graph: (77,16,0,4)