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A079754
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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'.
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7
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0, 1, 8, 54, 388, 3119, 28092, 280948, 3090464, 37085613, 482113024, 6749582402, 101243736108, 1619899777819, 27538296223028, 495689332014624, 9418097308277992, 188361946165559993, 3955600869476760024
(list; graph; refs; listen; history; internal format)
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OFFSET
| 3,3
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COMMENTS
| The asymptotic value for large n is 0.07742...*n! See also comment for A079884.
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REFERENCES
| See under A079884
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LINKS
| Hugo Pfoertner, FORTRAN program for lexicographic permutation generation
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FORMULA
| a(3)=0, a(n) = n*a(n-1) + (n-2)*(n-3)/2 for n>=4 a(n) = A079753(n) - A079752(n)
For n>=3 a(n)=floor(c*n!-(n-3)/2) where c=limit n --> infinity a(n)/n!=0.077422742688567853... - Benoit Cloitre (benoit7848c(AT)orange.fr), Jan 20 2003
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MATHEMATICA
| a[3] = 0; a[n_] := n*a[n - 1] + (n - 2)*(n - 3)/2; Table[a[n], {n, 3, 21}]
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PROG
| FORTRAN program available at link
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CROSSREFS
| Cf. A079884, A079750, A079751, A079752, A079753, A079755, A079756.
Sequence in context: A154235 A201640 A002775 * A142703 A138403 A013499
Adjacent sequences: A079751 A079752 A079753 * A079755 A079756 A079757
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KEYWORD
| nonn
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AUTHOR
| Hugo Pfoertner (hugo(AT)pfoertner.org), Jan 16 2003
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EXTENSIONS
| Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 22 2003
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