Number of point-self-dual nets with 2n nodes. Also number of directed 2-multigraphs with loops on n nodes.

A004105

Number of point-self-dual nets with 2n nodes. Also number of directed 2-multigraphs with loops on n nodes.

Terms

    a(0) =1a(1) =3a(2) =45a(3) =3411a(4) =1809459a(5) =7071729867

External references