A289987 Number of unlabeled connected loopless multigraphs with n nodes of degree less than n.

0, 1, 1, 2, 12, 146, 5847, 716141, 300635753, 430472002801, 2117649544384420, 36154420408979339192, 2165755991529764630384554, 459803603042851200545393118005

Offset: 0

Author

Natan Arie Consigli, Aug 19 2017

Keywords

• nonn
• more

Comments

Multigraphs are loopless.

Examples

			From _Gheorghe Coserea_, Oct 11 2017: (Start)
For n=4 the a(4)=12 solutions are:
o--o--o--o   o==o--o--o   o--o==o--o   o==o--o==o
o--o         o==o         o==o
|  |         |  |         |  |
o--o         o--o         o==o
o--o         o==o
| /          | /
|/           |/
o--o         o--o
o---o        o--o         o--o--o
|\ /|        | /|            |
| x |        |/ |            o
|/ \|        o--o
o---o
(End)
		

Crossrefs

A diagonal of A334546.

Cf. A001349, A289988.

Programs

nauty

for n in {1..8}; do geng -c -D$[${n}-1] ${n} -q | multig -m$[${n}-1] -D$[${n}-1] -u; done

Extensions

a(9)-a(13) from Andrew Howroyd, May 05 2020