Incidence graphs of the complementary designs of Hadamard $(15,7,3)$-designs.
The incidence graph of the complement of $PG(3,2)$ is the first graph in each file.
| Number of vertices: | $30$ |
| Diameter: | $3$ |
| Intersection array: | $\{8,7,4;1,4,8\}$ |
| Spectrum: | $8^1 2^{14} (-2)^{14} (-8)^1$ |
| Distance-transitive: | $PG(3,2)$ only |
| Bipartite |