login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A098639
Consider the family of directed multigraphs enriched by the species of odd sets. Sequence gives number of those multigraphs with n labeled arcs.
3
1, 1, 6, 69, 1230, 30663, 1005692, 41571127, 2099861244, 126607647073, 8945129371976, 729628409684925, 67868881258920424, 7125522244948969319, 837004398237510194704, 109173596976047915341823, 15708090522743045757716496, 2478722722731315203268137729
OFFSET
0,3
REFERENCES
G. Paquin, Dénombrement de multigraphes enrichis, Mémoire, Math. Dept., Univ. Québec à Montréal, 2004.
LINKS
G. Paquin, Dénombrement de multigraphes enrichis, Mémoire, Math. Dept., Univ. Québec à Montréal, 2004. [Cached copy, with permission]
FORMULA
E.g.f.: B(sinh(x)) where B(x) is the e.g.f. of A014505. - Andrew Howroyd, Jan 12 2021
PROG
(PARI) \\ EnrichedGdSeq defined in A098623.
EnrichedGdSeq(sinh(x + O(x*x^20))) \\ Andrew Howroyd, Jan 12 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Oct 26 2004
EXTENSIONS
Terms a(12) and beyond from Andrew Howroyd, Jan 12 2021
STATUS
approved