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 A029706 Sum C(n,k)*b(k), k=1..n, where b(k) is given by A001861. 1
 2, 10, 46, 226, 1214, 7106, 44958, 305090, 2206398, 16913986, 136823262, 1163490498, 10366252030, 96491364674, 935976996126, 9440144423874, 98800604237118, 1071092025420866, 12008090971866206, 139014305916844738 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS Jacques Carlier and Corinne Lucet, A decomposition algorithm for network reliability evaluation. In First International Colloquium on Graphs and Optimization (GOI), 1992 (Grimentz). Discrete Appl. Math. 65 (1996), 141-156 (see page 153 and Fig 6). FORMULA E.g.f.: 1/2 - exp(x) + 1/2*exp(2*exp(x)-2). a(n-2) = A035009(n)-1. - Ralf Stephan, Jan 26 2004 MATHEMATICA a[n_] := Sum[Binomial[n, k]*BellB[k, 2], {k, 1, n}]; Table[a[n], {n, 1, 20}] (* Jean-François Alcover, Apr 26 2013 *) PROG (PARI) x='x+O('x^66); Vec(serlaplace(1/2-exp(x)+1/2*exp(2*exp(x)-2))) \\ Joerg Arndt, Apr 21 2013 (PARI) a(n) = sum(k=1, n, binomial(n, k)*sum(j=1, k, stirling(k, j, 2)*2^j)); \\ \\ Michel Marcus, Apr 26 2013 CROSSREFS Arises if one of the two kinds of boxes mentioned in A001861 may 'fail'. Sequence in context: A137193 A006213 A137635 * A191644 A009640 A191684 Adjacent sequences:  A029703 A029704 A029705 * A029707 A029708 A029709 KEYWORD nonn AUTHOR Andre Poenitz (andre.poenitz(AT)mathematik.tu-chemnitz.de) EXTENSIONS Added missing digit in the last term from Jean-François Alcover, Apr 26 2013 STATUS approved

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Last modified October 15 17:24 EDT 2019. Contains 328037 sequences. (Running on oeis4.)