0 votes 0 votes How many non-isomorphic directed graphs are there with $n$ vertices when $n$ is $2$ $3$ $4$ Graph Theory engineering-mathematics discrete-mathematics kenneth-rosen graph-theory + – swati96 asked Jun 18, 2018 • edited Mar 4, 2019 by Pooja Khatri swati96 325 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.