A007105 Number of labeled Eulerian 3-regular digraphs with n nodes.

1, 0, 0, 0, 1, 44, 7570, 1975560, 749649145, 399035751464, 289021136349036, 277435664056527360, 345023964977303838105, 545099236551025860229460, 1075595203804151695555622446

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn

Comments

Apparently this counts the binary variant (all elements in {0,1}) of A001500 with zero trace. - R. J. Mathar, May 16 2021

References

• R. W. Robinson, personal communication.
• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• Óscar González, Carlos Beltrán, and Ignacio Santamaría, On the Number of Interference Alignment Solutions for the K-User MIMO Channel with Constant Coefficients, arXiv preprint arXiv:1301.6196 [cs.IT], 2013-2014. - From _N. J. A. Sloane_, Feb 19 2013
• Jan Tóth and Ondřej Kuželka, Complexity of Weighted First-Order Model Counting in the Two-Variable Fragment with Counting Quantifiers: A Bound to Beat, arXiv:2404.12905 [cs.LO], 2024. See p. 18.

Crossrefs

Cf. A001500, A284990.