A graph 
is transitive if any three vertices 
such that edges 
imply 
. Unlabeled transitive digraphs are called digraph
topologies.
See also
Digraph Topology, Transitive Reduction
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Cite this as:
Weisstein, Eric W. "Transitive Digraph." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/TransitiveDigraph.html