A directed strongly regular graph is a simple directed graph with adjacency matrix 
such that the span of 
, the identity matrix 
,
and the unit matrix 
is closed under matrix
multiplication.
Directed Strongly Regular Graph
See also
Regular Graph, Simple Directed Graph, Simple Graph, Strongly Regular GraphExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Directed Strongly Regular Graph." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/DirectedStronglyRegularGraph.html