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
a(n) = 2^n*A020556(n). - Vladeta Jovovic, Aug 11 2005
E.g.f.: B(R(x)) where B(x) is the e.g.f. of A014505 and 1 + R(x) is the e.g.f. of A000079. - Andrew Howroyd, Jan 12 2021
PROG
R(n)={exp(2*x + O(x*x^n))}
EnrichedGdSeq(R(20)) \\ Andrew Howroyd, Jan 12 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Oct 26 2004
EXTENSIONS
More terms from Vladeta Jovovic, Aug 11 2005
Terms a(14) and beyond from Andrew Howroyd, Jan 12 2021
STATUS
approved