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A011912
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[ n(n-1)(n-2)/30 ].
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0
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0, 0, 0, 0, 0, 2, 4, 7, 11, 16, 24, 33, 44, 57, 72, 91, 112, 136, 163, 193, 228, 266, 308, 354, 404, 460, 520, 585, 655, 730, 812, 899, 992, 1091, 1196, 1309, 1428, 1554, 1687, 1827, 1976, 2132, 2296, 2468, 2648
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,6
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LINKS
| Index to sequences with linear recurrences with constant coefficients, signature (3,-3,1,0,1,-3,3,-1). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 15 2010]
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FORMULA
| a(n) = +3*a(n-1) -3*a(n-2) +a(n-3) +a(n-5) -3*a(n-6) +3*a(n-7) -a(n-8). G.f.: x^5*(x^2-2*x+2) / ( (-1+x)^4*(x^4+x^3+x^2+x+1) ). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 15 2010]
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MAPLE
| seq(floor(binomial(n, 3)/5), n=0..43); # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jan 12 2009]
seq(floor(binomial(n, 3)/5), n=0..43); # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jan 12 2009]
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MATHEMATICA
| Table[Floor[(n(n-1)(n-2))/30], {n, 0, 50}] (* or *) LinearRecurrence[ {3, -3, 1, 0, 1, -3, 3, -1}, {0, 0, 0, 0, 0, 2, 4, 7}, 50] (* From Harvey P. Dale, June 20 2011 *)
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CROSSREFS
| Sequence in context: A005253 A129339 A196719 * A063676 A099385 A120118
Adjacent sequences: A011909 A011910 A011911 * A011913 A011914 A011915
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KEYWORD
| nonn
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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