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 A053436 a(n) = n+1 + ceiling(n/2)*(ceiling(n/2)-1)*(ceiling(n/2)+1)/6. 1
 2, 3, 5, 6, 10, 11, 18, 19, 30, 31, 47, 48, 70, 71, 100, 101, 138, 139, 185, 186, 242, 243, 310, 311, 390, 391, 483, 484, 590, 591, 712, 713, 850, 851, 1005, 1006, 1178, 1179, 1370, 1371, 1582, 1583, 1815, 1816, 2070, 2071, 2348, 2349, 2650, 2651 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..5000 G. Giani, K. Strassburger, Multiple comparison procedures for optimally discriminating between good, equivalent and bad treatments with respect to a control, J. Statist. Planning Infer. 83 (No. 2, 2000), 413-440. Index entries for linear recurrences with constant coefficients, signature (1,3,-3,-3,3,1,-1). FORMULA a(n) = n + 1 + A000292(ceiling(n/2)-2). a(n) = a(n-1) +3 a(n-2) -3 a(n-3) -3 a(n-4) +3 a(n-5) +a(n-6) -a(n-7). - R. J. Mathar, Mar 11 2012 G.f.: x*(2+x-4*x^2-2*x^3+4*x^4+x^5-x^6)/((1-x)^4*(1+x)^3). - Colin Barker, Apr 02 2012 a(n) = (2*n^3+3*n^2+91*n+93-3*(n^2+n-1)*(-1)^n)/96. - Luce ETIENNE, Oct 22 2014 MATHEMATICA CoefficientList[Series[(2+x-4*x^2-2*x^3+4*x^4+x^5-x^6)/((1-x)^4*(1+x)^3), {x, 0, 50}], x] (* Vincenzo Librandi, Apr 28 2012 *) cn[n_]:=(Times@@(Ceiling[n/2]+{1, 0, -1}))/6+n+1; Array[cn, 50] (* or *) LinearRecurrence[{1, 3, -3, -3, 3, 1, -1}, {2, 3, 5, 6, 10, 11, 18}, 50] (* Harvey P. Dale, Mar 27 2013 *) PROG (MAGMA) [n+1 + Ceiling(n/2)*(Ceiling(n/2)-1)*(Ceiling(n/2)+1)/6: n in [1..50]]; // Vincenzo Librandi, Apr 28 2012 (PARI) for(n=1, 30, print1((2*n^3+3*n^2+91*n+93-3*(n^2+n-1)*(-1)^n)/96, ", ")) \\ G. C. Greubel, May 26 2018 CROSSREFS Cf. A000292. Sequence in context: A024560 A000039 A302600 * A057546 A138587 A099350 Adjacent sequences:  A053433 A053434 A053435 * A053437 A053438 A053439 KEYWORD easy,nonn AUTHOR Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Jan 11 2000 STATUS approved

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Last modified October 17 21:34 EDT 2019. Contains 328133 sequences. (Running on oeis4.)