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 A084358 Lists of sets of lists. 8
 1, 1, 5, 37, 363, 4441, 65133, 1114009, 21771851, 478658101, 11692343253, 314170940293, 9209104364331, 292435635165649, 10000637145321917, 366427621403088433, 14321135069200849515, 594696814358067968461, 26147933188037724372069 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS This sequence and -A000262 with the first term set to 1 form a reciprocal pair under the list partition transform and associated operations described in A133314. - Tom Copeland, Oct 21 2007 REFERENCES T. S. Motzkin, Sorting numbers ...: for a link to an annotated scanned version of this paper see A000262. T. S. Motzkin, Sorting numbers for cylinders and other classification numbers, in Combinatorics, Proc. Symp. Pure Math. 19, AMS, 1971, pp. 167-176. LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..200 T.-X. He, A symbolic operator approach to power series transformation-expansion formulas, JIS 11 (2008) 08.2.7 M. Janjic, Some classes of numbers and derivatives, JIS 12 (2009) 09.8.3 N. J. A. Sloane and Thomas Wieder, The Number of Hierarchical Orderings, Order 21 (2004), 83-89. FORMULA a(n) = n!*Lag{n,(.)!*Lag[.,P(.,2),0],-1} = P(n,2) - n*P(n-1,2) umbrally, where P(j,t) are the polynomials in A131758 and Lag(n,x,a) are the associated Laguerre polynomials of order a; that is, the sequence is given by an iterated combinatorial Laguerre transform, of mixed order, of a set of polynomials related to the polylogarithms, which reduces to a simple finite difference. - Tom Copeland, Sep 30 2007 E.g.f.: 1/(2-exp(x/(1-x))). Lah transform of preferential arrangements: Sum_{k=0..n} n!/k!*binomial(n-1, k-1)*A000670(k). - Vladeta Jovovic, Sep 28 2003 a(n) ~ n! * (1+log(2))^(n-1) / (2*(log(2))^(n+1)). - Vaclav Kotesovec, Oct 08 2013 MAPLE with(combstruct); SeqSetSeqL := [T, {T=Sequence(S), S=Set(U, card >= 1), U=Sequence(Z, card >=1)}, labeled]; [seq(count(%, size=j), j=1..12)]; MATHEMATICA With[{nn=20}, CoefficientList[Series[1/(2-Exp[x/(1-x)]), {x, 0, nn}], x] Range[ 0, nn]!] (* Harvey P. Dale, Apr 16 2013 *) PROG (PARI) x='x+O('x^30); Vec(serlaplace(1/(2-exp(x/(1-x))))) \\ G. C. Greubel, May 16 2018 (MAGMA) m:=25; R:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(1/(2-Exp(x/(1-x))))); [Factorial(n-1)*b[n]: n in [1..m]]; // G. C. Greubel, May 16 2018 CROSSREFS Sequence in context: A112698 A234953 A025168 * A050351 A129137 A276232 Adjacent sequences:  A084355 A084356 A084357 * A084359 A084360 A084361 KEYWORD nonn AUTHOR N. J. A. Sloane, Jun 22 2003 STATUS approved

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Last modified April 16 02:35 EDT 2021. Contains 343030 sequences. (Running on oeis4.)