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Consider the family of multigraphs enriched by the species of parts. Sequence gives number of those multigraphs with n labeled edges.
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%I #13 Jan 12 2021 18:56:31

%S 1,2,12,128,2224,56000,1880832,79985792,4161468928,258415579648,

%T 18793653411840,1576791247634432,150745211441983488,

%U 16253127712884269056,1959064946185017851904,262002352633857351942144,38624060984664180255621120,6240304185636529522872025088

%N Consider the family of multigraphs enriched by the species of parts. Sequence gives number of those multigraphs with n labeled edges.

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

%H Andrew Howroyd, <a href="/A098628/b098628.txt">Table of n, a(n) for n = 0..100</a>

%H G. Paquin, <a href="/A038205/a038205.pdf">Dénombrement de multigraphes enrichis</a>, Mémoire, Math. Dept., Univ. Québec à Montréal, 2004. [Cached copy, with permission]

%F E.g.f.: B(R(x)) where B(x) is the e.g.f. of A014500 and 1 + R(x) is the e.g.f. of A000079. - _Andrew Howroyd_, Jan 12 2021

%o (PARI) \\ R(n) is A000079 as e.g.f.; EnrichedGnSeq defined in A098620.

%o R(n)={exp(2*x + O(x*x^n))}

%o EnrichedGnSeq(R(20)) \\ _Andrew Howroyd_, Jan 12 2021

%Y Cf. A000079, A014500, A098620, A098629, A098630, A098631.

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Oct 26 2004

%E Terms a(11) and beyond from _Andrew Howroyd_, Jan 12 2021