This graph is the unique $\mathrm{SRG}(28,15,6,10)$. It is the complement of the Johnson graph $\mathrm{J}(8,2)$.
Number of vertices: | $28$ |
Diameter: | $2$ |
Intersection array: | $\{15,8;1,10\}$ |
Spectrum: | $15^1 1^{20} (-5)^7$ |
Automorphism group: | $\mathrm{S}_8$ |
Distance-transitive: | Yes |
Primitive |