Consider the family of directed multigraphs enriched by the species of odd sets. Sequence gives number of those multigraphs with n labeled arcs.

A098639

Consider the family of directed multigraphs enriched by the species of odd sets. Sequence gives number of those multigraphs with n labeled arcs.

Terms

    a(0) =1a(1) =1a(2) =6a(3) =69a(4) =1230a(5) =30663a(6) =1005692a(7) =41571127a(8) =2099861244a(9) =126607647073

External references