A020562 - OEIS

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Table of n, a(n) for n=0..16.

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]

FORMULA

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

CROSSREFS

Cf. A014500.

Sequence in context: A007767 A075820 A145081 * A193161 A364630 A318987

Adjacent sequences: A020559 A020560 A020561 * A020563 A020564 A020565

KEYWORD

nonn

AUTHOR

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

STATUS

approved