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 A000268 E.g.f.: -log(1+log(1+log(1-x))). (Formerly M3003 N1218) 10
 1, 3, 15, 105, 947, 10472, 137337, 2085605, 36017472, 697407850, 14969626900, 352877606716, 9064191508018, 252024567201300, 7542036496650006, 241721880399970938, 8261159383595659128, 299916384730043070880 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 REFERENCES J. Ginsburg, Iterated exponentials, Scripta Math., 11 (1945), 340-353. N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS T. D. Noe, Table of n, a(n) for n=1..100 P. J. Cameron, Sequences realized by oligomorphic permutation groups, J. Integ. Seqs. Vol. 3 (2000), #00.1.5. Jekuthiel Ginsburg, Iterated exponentials, Scripta Math., 11 (1945), 340-353. [Annotated scanned copy] INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 299 Kruchinin Vladimir Victorovich, Composition of ordinary generating functions, arXiv:1009.2565 [math.CO], 2010. FORMULA a(n) = sum((m-1)!*(-1)^(n+m)*sum(stirling1(n, k)*stirling1(k, m), k,m,n), m,1,n), n>0. - Vladimir Kruchinin, Sep 14 2010 MATHEMATICA max = 20; CoefficientList[-Log[1 + Log[1 + Log[1 - x]]]/x + O[x]^max, x] * Range[max]! (* Jean-François Alcover, Feb 06 2016 *) PROG (PARI) a(n) = sum(m=1, n, (m-1)!*(-1)^(n+m)*sum(k=m, n, stirling(n, k, 1)*stirling(k, m, 1))); \\ Michel Marcus, Feb 06 2016 CROSSREFS a(n)=|A039815(n, 1)| (first column of triangle). Cf. A003713, A000310, A000359, A000406, A001765. Sequence in context: A294001 A294002 A001147 * A207818 A118750 A070826 Adjacent sequences:  A000265 A000266 A000267 * A000269 A000270 A000271 KEYWORD nonn AUTHOR EXTENSIONS Revised description from Christian G. Bower, Aug 15 1998 STATUS approved

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Last modified October 23 12:04 EDT 2019. Contains 328345 sequences. (Running on oeis4.)