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 A140325 a(n) = binomial(n+8,8) * 2^n. 12
 1, 18, 180, 1320, 7920, 41184, 192192, 823680, 3294720, 12446720, 44808192, 154791936, 515973120, 1666990080, 5239111680, 16066609152, 48199827456, 141764198400, 409541017600, 1163958681600, 3259084308480, 9001280471040 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS With a different offset, number of n-permutations (n>=8) of 3 objects: u, v, z with repetition allowed, containing exactly eight (8) u's. See example. Number of 8D hypercubes in an n-dimensional hypercube. [Zerinvary Lajos, Jan 29 2010] LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..400 M. Janjic and B. Petkovic, A Counting Function, arXiv 1301.4550, 2013 FORMULA G.f.: 1/(1-2*x)^9. - R. J. Mathar, Feb 11 2010 a(n) = 2*a(n-1) + A054851(n-1). - Ruskin Harding, May 12 2013 a(n) = Sum_{i=8..n+8} binomial(i,8)*binomial(n+8,i). Example: for n=6, a(6) = 1*3003 + 9*2002 + 45*1001 + 165*364 + 495*91 + 1287*14 + 3003*1 = 192192. - Bruno Berselli, Mar 23 2018 EXAMPLE Example: a(1)=18 because we have uuuuuuuuv, uuuuuuuvu, uuuuuuvuu, uuuuuvuuu, uuuuvuuuu, uuuvuuuuu, uuvuuuuuu, uvuuuuuuu, vuuuuuuuu, uuuuuuuuz, uuuuuuuzu, uuuuuuzuu, uuuuuzuuu, uuuuzuuuu, uuuzuuuuu, uuzuuuuuu, uzuuuuuuu and zuuuuuuu. MAPLE seq(binomial(n+8, 8)*2^n, n=0..28); MATHEMATICA Table[Binomial[n + 8, 8] 2^n, {n, 0, 20}] (* Zerinvary Lajos, Jan 29 2010 *) PROG (Sage) [lucas_number2(n, 2, 0)*binomial(n, 8)/256 for n in xrange(8, 30)] [Zerinvary Lajos, Mar 10 2009] (MAGMA) [2^n*Binomial(n+8, 8): n in [0..30]]; // Vincenzo Librandi, Oct 14 2011 CROSSREFS Sequence in context: A071910 A121038 A004410 * A199299 A155669 A160954 Adjacent sequences:  A140322 A140323 A140324 * A140326 A140327 A140328 KEYWORD nonn,easy AUTHOR Zerinvary Lajos, Jun 23 2008 STATUS approved

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Last modified August 17 06:56 EDT 2018. Contains 313810 sequences. (Running on oeis4.)