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 A082403 E.g.f.: 1-1/B(x) where B(x) is e.g.f. for A003024. 1
 0, 1, 1, 13, 373, 24061, 3430021, 1085594413, 765444156373, 1199327541421981, 4150826776751106181, 31511604323119334675053, 521181162682913685911315413, 18663030289006900328937074926621 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 REFERENCES R. W. Robinson, Counting labeled acyclic digraphs, p. 264 of F. Harary, editor, New Directions in the Theory of Graphs. Academic Press, NY, 1973 LINKS Andrew Howroyd, Table of n, a(n) for n = 0..50 MATHEMATICA m = 20; b[0] = b[1] = 1; b[n_] := b[n] = Sum[-(-1)^k Binomial[n, k] 2^(k (n-k)) b[n-k], {k, 1, n}]; B[x_] = Sum[b[n] x^n/n!, {n, 0, m}]; CoefficientList[1 - 1/B[x] + O[x]^(m+1), x] Range[0, m]! (* Jean-François Alcover, Jan 24 2020 *) PROG (PARI) \\ here G(n) gives A003024 as e.g.f. G(n)={my(v=vector(n+1)); v[1]=1; for(n=1, n, v[n+1]=sum(k=1, n, -(-1)^k*2^(k*(n-k))*v[n-k+1]/k!))/n!; Ser(v)} { concat([0], Vec(serlaplace(1-1/G(15)))) } \\ Andrew Howroyd, Sep 10 2018 CROSSREFS Cf. A003024. Sequence in context: A009040 A009085 A012013 * A171656 A320458 A320635 Adjacent sequences:  A082400 A082401 A082402 * A082404 A082405 A082406 KEYWORD nonn AUTHOR Vladeta Jovovic, Apr 15 2003 STATUS approved

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Last modified August 10 00:32 EDT 2022. Contains 356026 sequences. (Running on oeis4.)