A308239 Number of isomorphism classes of connected Eulerian oriented graphs with n vertices.

1, 1, 0, 1, 1, 4, 16, 175, 5274, 434017, 90658149, 48825116761, 68579602126387, 254236892409251687, 2512196983110257299898, 66738846701458593981832314, 4802164152196181961357340585741, 942009012794429918939576183310877477, 506665422212653541096106256584713063500057

Offset: 0

Author

Alois P. Heinz, May 16 2019

Keywords

• nonn
• hard

Comments

Loops and 2-cycles are not permitted. Eulerian means that each vertex has equal in-degree and out-degree.

Crossrefs

Cf. A308161.

Formula

Inverse Euler transform of A308161.

Extensions

Terms a(12) and beyond from Andrew Howroyd, Apr 10 2020