179228736

Appears in sequences

• Number of relational systems on n nodes. Also number of directed 3-multigraphs with loops on n nodes.at n=3A001374
• Number of self-complementary digraphs with n nodes.at n=8A003086
• Number of orbits of the action g*b = b o (g x g) of the group of permutations g of an n-element set S on the set of closed binary operations b on S.at n=4A154238
• Number of unlabeled general directed hypergraphs of order n.at n=3A222420