Consider the family of directed multigraphs enriched by the species of parts. Sequence gives number of those multigraphs with n labeled loops and arcs.

A098630

Consider the family of directed multigraphs enriched by the species of parts. Sequence gives number of those multigraphs with n labeled loops and arcs.

Terms

    a(0) =1a(1) =4a(2) =60a(3) =1624a(4) =66240a(5) =3711200a(6) =269670208a(7) =24435113216

External references