This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A079753 #14 Jan 11 2013 15:25:21
%S A079753 0,3,21,136,967,7757,69841,698446,7682951,92195467,1198541137,
%T A079753 16779575996,251693640031,4027098240601,68460670090337,
%U A079753 1232292061626202,23413549170897991,468270983417959991,9833690651777160001
%N A079753 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 total executions of step L3.1'.
%C A079753 The asymptotic value for large n is 0.19247...*n! = (e/2-7/6)*n!. See also comment for A079884.
%D A079753 See under A079884
%H A079753 Hugo Pfoertner, <a href="http://www.randomwalk.de/sequences/lpgcount.txt">FORTRAN program for lexicographic permutation generation</a>
%F A079753 a(3)=0, a(n)= n*a(n-1) + (n-1)*(n-2)/2 for n>=4 a(n) = A079752(n) + A079754(n)
%F A079753 For n>=3, a(n)=floor(c*n!-(n-1)/2) where c=limit n-->infinity a(n)/n!= 0.192474247562855951... - _Benoit Cloitre_, Jan 20 2003
%t A079753 a[3] = 0; a[n_] := n*a[n - 1] + (n - 1)*(n - 2)/2; Table[a[n], {n, 3, 21}]
%o A079753 FORTRAN program available at link
%Y A079753 Cf. A079884, A079750, A079751, A079752, A079754, A079755, A079756.
%K A079753 nonn
%O A079753 3,2
%A A079753 _Hugo Pfoertner_, Jan 16 2003
%E A079753 Edited and extended by _Robert G. Wilson v_, Jan 22 2003