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0, 6, 48, 342, 2400, 16806, 117648, 823542, 5764800, 40353606, 282475248, 1977326742, 13841287200, 96889010406, 678223072848, 4747561509942, 33232930569600, 232630513987206, 1628413597910448, 11398895185373142
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Numbers n for which the expression 7^n/(n+1) is an integer. - Paolo P. Lava (paoloplava(AT)gmail.com), May 29 2006
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 0..500
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FORMULA
| G.f.: 1/(1-7*x)-1/(1-x). E.g.f.: exp(7*x)-exp(x). [From Mohammad K. Azarian (azarian(AT)evansville.edu), Jan 14 2009]
a(n+1) = 7*a(n) + 6. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Nov 22 2009]
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PROG
| (MAGMA) [7^n-1: n in [0..25]]; // Vincenzo Librandi, Jul 03 2011
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CROSSREFS
| Sequence in context: A165758 A166152 A049316 * A052571 A052625 A155130
Adjacent sequences: A024072 A024073 A024074 * A024076 A024077 A024078
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KEYWORD
| nonn,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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