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 A099694 Consider the family of directed multigraphs enriched by the species of directed sets. Sequence gives number of those multigraphs with n labeled loops and arcs. 3
 1, 2, 17, 244, 5283, 156092, 5954547, 282221828, 16159327961, 1094056231572, 86116276633357, 7773114989571400, 795480206815177651, 91417037615848058160, 11701283925663217478843, 1656436690705751478232180, 257730676653629520748175377, 43837005194184348815823808500 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 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 A014507. - Andrew Howroyd, Jan 12 2021 PROG (PARI) \\ R(n) is e.g.f. of 1, 1, 2, 2, 2, ...; EnrichedGdlSeq defined in A098622. R(n)={2*exp(x + O(x*x^n)) - x - 1} EnrichedGdlSeq(R(20)) \\ Andrew Howroyd, Jan 12 2021 CROSSREFS Cf. A014507, A098622, A099692, A099693, A099695. Sequence in context: A240999 A319947 A342205 * A099698 A218681 A098622 Adjacent sequences:  A099691 A099692 A099693 * A099695 A099696 A099697 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 September 19 08:05 EDT 2021. Contains 347556 sequences. (Running on oeis4.)