Consider the family of directed multigraphs enriched by the species of set partitions. Sequence gives number of those multigraphs with n labeled arcs.
A098623
Consider the family of directed multigraphs enriched by the species of set partitions. Sequence gives number of those multigraphs with n labeled arcs.
Terms
- a(0) =1a(1) =1a(2) =8a(3) =109a(4) =2229a(5) =62684a(6) =2289151a(7) =104344153a(8) =5767234550a(9) =378073098155
External references
- oeis: A098623