A020562 Number of cyclic multigraphs on n labeled edges (without loops).

1, 1, 3, 17, 152, 1933, 32608, 695657, 18148533, 564860131, 20581455139, 864802010595, 41392831046804, 2233799248861031, 134737655762330602, 9015762313899965851, 664889968074287179739

Offset: 0

Author

Gilbert Labelle (gilbert(AT)lacim.uqam.ca), Simon Plouffe

Keywords

• nonn

Links

• G. Labelle, Counting enriched multigraphs according to the number of their edges (or arcs), Discrete Math., 217 (2000), 237-248.
• G. Paquin, Dénombrement de multigraphes enrichis, Mémoire, Math. Dept., Univ. Québec à Montréal, 2004. [Cached copy, with permission]

Crossrefs

Cf. A014500.

Formula

a(n) = Sum_{k=0..n} (-1)^(n-k)*Stirling1(n, k)*A014500(k). - Sean A. Irvine, Apr 25 2019