A053515 Number of connected directed 3-multigraphs on n nodes.
1, 9, 710, 702995, 9167621626, 1601362624429243, 3837877364912125546166, 128777253726443722899317880176, 61454877368531170511811727162658812448, 422314689334495256777424027741114845781285378061
Offset: 1
Links
- Marko Riedel, Table of n, a(n) for n = 1..50 (first 10 terms from Vladeta Jovovic)
- Marko Riedel, Maple implementation of a recurrence for the number of connected directed k-multigraphs on n nodes