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 A005388 Number of degree-n permutations of order a power of 2. (Formerly M1293) 15
 1, 1, 2, 4, 16, 56, 256, 1072, 11264, 78976, 672256, 4653056, 49810432, 433429504, 4448608256, 39221579776, 1914926104576, 29475151020032, 501759779405824, 6238907914387456, 120652091860975616, 1751735807564578816, 29062253310781161472, 398033706586943258624 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Differs from A053503 first at n=32. - Alois P. Heinz, Feb 14 2013 REFERENCES N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see Example 5.2.10. LINKS Alois P. Heinz, Table of n, a(n) for n = 0..200 J. M. Møller, Euler characteristics of equivariant subcategories, arXiv preprint arXiv:1502.01317, 2015. See page 20. L. Moser and M. Wyman, On solutions of x^d = 1 in symmetric groups, Canad. J. Math., 7 (1955), 159-168. A. Recski, Enumerating partitional matroids, Preprint. A. Recski & N. J. A. Sloane, Correspondence, 1975 FORMULA E.g.f.: exp(Sum(x^(2^m)/2^m, m >=0)). MAPLE a:= proc(n) option remember; `if`(n<0, 0, `if`(n=0, 1,        add(mul(n-i, i=1..2^j-1)*a(n-2^j), j=0..ilog2(n))))     end: seq(a(n), n=0..25);  # Alois P. Heinz, Feb 14 2013 MATHEMATICA max = 23; CoefficientList[ Series[ Exp[ Sum[x^2^m/2^m, {m, 0, max}]], {x, 0, max}], x]*Range[0, max]! (* Jean-François Alcover, Sep 10 2013 *) CROSSREFS Cf. A000085, A001470, A001472, A053495-A053505. Cf. A053503. Sequence in context: A306519 A001472 A053498 * A053503 A308381 A153957 Adjacent sequences:  A005385 A005386 A005387 * A005389 A005390 A005391 KEYWORD nonn,nice,easy AUTHOR STATUS approved

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Last modified October 15 21:17 EDT 2019. Contains 328038 sequences. (Running on oeis4.)