Search: id:A001472
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%I A001472 M1292 N0495
%S A001472 1,1,2,4,16,56,256,1072,6224,33616,218656,1326656,9893632,70186624,
%T A001472 574017536,4454046976,40073925376,347165733632,3370414011904,31426411211776,
%U A001472 328454079574016,3331595921852416,37125035407900672,400800185285464064
%N A001472 Number of degree-n permutations of order dividing 4.
%D A001472 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A001472 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A001472 L. Moser and M. Wyman, On solutions of x^d = 1 in symmetric groups, Canad. 
               J. Math., 7 (1955), 159-168.
%D A001472 R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see 
               Example 5.2.10.
%H A001472 T. D. Noe, <a href="b001472.txt">Table of n, a(n) for n=0..200</a>
%H A001472 INRIA Algorithms Project, <a href="http://algo.inria.fr/bin/encyclopedia?Search=ECSnb&argsearch=25">
               Encyclopedia of Combinatorial Structures 25</a>
%F A001472 E.g.f.: exp(x+1/2*x^2+1/4*x^4).
%F A001472 a(0)=1, a(1)=1, a(2)=2, a(3)=4, a(n)=a(n-1)+(n-1)*a(n-2)+(n^3-6n^2+11n-6)*a(n-4) 
               for n>3. [From H. Palsdottir (hronn07(AT)ru.is), Sep 19 2008]
%Y A001472 Cf. A000085, A001470, A053495.
%Y A001472 Sequence in context: A104354 A153948 A010362 this_sequence A053498 A005388 
               A053503
%Y A001472 Adjacent sequences: A001469 A001470 A001471 this_sequence A001473 A001474 
               A001475
%K A001472 nonn,nice,easy
%O A001472 0,3
%A A001472 N. J. A. Sloane (njas(AT)research.att.com) and J. H. Conway (conway(AT)math.princeton.edu)

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