A053515 Number of connected directed 3-multigraphs on n nodes.

1, 9, 710, 702995, 9167621626, 1601362624429243, 3837877364912125546166, 128777253726443722899317880176, 61454877368531170511811727162658812448, 422314689334495256777424027741114845781285378061

Offset

1,2

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

Crossrefs

Cf. A053468, A053466.

Sequence in context: A109061 A332169 A282181 * A120816 A161585 A255259

Adjacent sequences: A053512 A053513 A053514 * A053516 A053517 A053518

Keyword

easy,nonn

Author

Vladeta Jovovic, Jan 14 2000

Status

approved