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 A228509 a(n) = binomial(n^2+n+1,n) * (n+1) / (n^2+n+1) for n>=0. 0
 1, 2, 9, 88, 1425, 32886, 992446, 37106784, 1657248417, 86128357150, 5107663394691, 340427678198400, 25194445531808735, 2050156960934135340, 181938723871328671500, 17487609556155439051136, 1809886850192627028383553, 200670984392566362698014110, 23730570474434159458296269953 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Table of n, a(n) for n=0..18. FORMULA a(n) = (n+1)*A135862(n). EXAMPLE G.f.: A(x) = 1 + 2*x + 9*x^2 + 88*x^3 + 1425*x^4 + 32886*x^5 +... MATHEMATICA Table[(Binomial[n^2+n+1, n](n+1))/(n^2+n+1), {n, 0, 20}] (* Harvey P. Dale, Oct 13 2015 *) PROG (PARI) {a(n)=binomial(n^2+n+1, n)*(n+1)/(n^2+n+1)} for(n=0, 20, print1(a(n), ", ")) CROSSREFS Cf. A135862, A135860. Sequence in context: A259794 A347013 A132431 * A361607 A001192 A006120 Adjacent sequences: A228506 A228507 A228508 * A228510 A228511 A228512 KEYWORD nonn AUTHOR Paul D. Hanna, Aug 23 2013 STATUS approved

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Last modified May 22 10:58 EDT 2024. Contains 372745 sequences. (Running on oeis4.)