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%I #15 Sep 02 2017 14:39:17
%S 0,1,8,54,388,3119,28092,280948,3090464,37085613,482113024,6749582402,
%T 101243736108,1619899777819,27538296223028,495689332014624,
%U 9418097308277992,188361946165559993,3955600869476760024
%N Operation count to create all permutations of n distinct elements using the "streamlined" version of Algorithm L (lexicographic permutation generation) from Knuth's The Art of Computer Programming, Vol. 4, chapter 7.2.1.2. Sequence gives number of times l has to be repeatedly decreased in step L3.1'.
%C The asymptotic value for large n is 0.07742...*n! See also comment for A079884.
%C Lim_{n->infinity} a(n)/n! = 3*e/2 - 4. - _Hugo Pfoertner_, Sep 02 2017
%D See under A079884
%H Hugo Pfoertner, <a href="http://www.randomwalk.de/sequences/lpgcount.txt">FORTRAN program for lexicographic permutation generation</a>
%F a(3)=0, a(n) = n*a(n-1) + (n-2)*(n-3)/2 for n>=4 a(n) = A079753(n) - A079752(n)
%F For n>=3 a(n)=floor(c*n!-(n-3)/2) where c=limit n --> infinity a(n)/n!=0.077422742688567853... - _Benoit Cloitre_, Jan 20 2003
%t a[3] = 0; a[n_] := n*a[n - 1] + (n - 2)*(n - 3)/2; Table[a[n], {n, 3, 21}]
%o FORTRAN program available at link
%Y Cf. A079884, A079750, A079751, A079752, A079753, A079755, A079756, A196533.
%K nonn
%O 3,3
%A _Hugo Pfoertner_, Jan 16 2003
%E Edited and extended by _Robert G. Wilson v_, Jan 22 2003
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