Properties
In the Shrikhande graph, any two vertices I and J have two distinct neighbors in common (excluding the two vertices I and J themselves), which holds true whether or not I is adjacent to J. In other words, its parameters for being strongly regular are: {16,6,2,2}, with, this equality implying that the graph is associated with a symmetric BIBD. It shares these parameters with a different graph, the 4×4 rook's graph.
The Shrikhande graph is locally hexagonal; that is, the neighbors of each vertex form a cycle of six vertices. As with any locally cyclic graph, the Shrikhande graph is the 1-skeleton of a Whitney triangulation of some surface; in the case of the Shrikhande graph, this surface is a torus in which each vertex is surrounded by six triangles. Thus, the Shrikhande graph is a toroidal graph. The dual of this embedding is the Dyck graph, a cubic symmetric graph.
The Shrikhande graph is not a distance-transitive graph. It is the smallest distance-regular graph that is not distance-transitive.
The automorphism group of the Shrikhande graph is of order 192. It acts transitively on the vertices, on the edges and on the arcs of the graph. Therefore the Shrikhande graph is a symmetric graph.
The characteristic polynomial of the Shrikhande graph is : . Therefore the Shrikhande graph is an integral graph: its spectrum consists entirely of integers.
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