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A099692 Consider the family of multigraphs enriched by the species of directed sets. Sequence gives number of those multigraphs with n labeled edges. 3
1, 1, 4, 23, 220, 3016, 55011, 1265824, 35496711, 1183686987, 46072834777, 2062557088117, 104926356851165, 6004962409831577, 383331023991407286, 27094756978689827593, 2107021273883402908850, 179261681391054814324774, 16602830645109035036038335 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

REFERENCES

G. Paquin, Dénombrement de multigraphes enrichis, Mémoire, Math. Dept., Univ. Québec à Montréal, 2004.

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..100

G. Paquin, Dénombrement de multigraphes enrichis, Mémoire, Math. Dept., Univ. Québec à Montréal, 2004. [Cached copy, with permission]

FORMULA

E.g.f.: B(2*exp(x) - x - 2) where B(x) is the e.g.f. of A014500. - Andrew Howroyd, Jan 12 2021

PROG

(PARI) \\ R(n) is e.g.f. of 1, 1, 2, 2, 2, 2, ...; EnrichedGnSeq defined in A098620.

R(n)={2*exp(x + O(x*x^n)) - x - 1}

EnrichedGnSeq(R(20)) \\ Andrew Howroyd, Jan 12 2021

CROSSREFS

Cf. A000110, A014500, A098620, A099693, A099694, A099695.

Sequence in context: A056785 A188404 A105747 * A283499 A305787 A295234

Adjacent sequences:  A099689 A099690 A099691 * A099693 A099694 A099695

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Oct 26 2004

EXTENSIONS

Terms a(11) and beyond from Andrew Howroyd, Jan 12 2021

STATUS

approved

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Last modified October 22 16:15 EDT 2021. Contains 348174 sequences. (Running on oeis4.)