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A002776
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Terms in certain determinants.
(Formerly M3972 N1642)
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1
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1, 5, 34, 258, 2136, 19320, 190800, 2051280, 23909760, 300827520, 4067884800, 58877280000, 908666035200, 14901260774400, 258832346572800, 4748165630208000, 91746433658880000, 1862735060938752000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| a(n) equals (n+1)^2 times the permanent of the (n+1) X (n+1) matrix with 1/(n+1) in the top right corner, 1/(n+1) in the bottom left corner, and 1's everywhere else. - John M. Campbell, (jmaxwellcampbell(AT)gmail.com), May 25, 2011
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REFERENCES
| J. D. H. Dickson, Discussion of two double series arising from the number of terms in determinants of certain forms, Proc. London Math. Soc., 10 (1879), 120-122.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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FORMULA
| a(n)=(n^3+n^2+2*n+1)*n!
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MATHEMATICA
| Table[(n^3+n^2+2n+1)n!, {n, 0, 30}] (* From Harvey P. Dale, Oct 28 2011 *)
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CROSSREFS
| Cf. A047922.
Sequence in context: A080503 A078284 A083987 * A081342 A058248 A116435
Adjacent sequences: A002773 A002774 A002775 * A002777 A002778 A002779
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KEYWORD
| nonn,easy,nice
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
| Edited by Dean Hickerson (dean.hickerson(AT)yahoo.com), Sep 20 2002
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