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 A063021 Reversion of y - y^2 - y^5. 0
 0, 1, 1, 2, 5, 15, 49, 168, 594, 2150, 7931, 29718, 112814, 432957, 1677050, 6547856, 25742454, 101819100, 404885630, 1617725010, 6491294600, 26147434885, 105691660110, 428578242900, 1742925259725, 7106942278683 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS Vladimir Kruchinin, The method for obtaining expressions for coefficients of reverse generating functions, arXiv:1211.3244 [math.CO], 2012. FORMULA a(n) = sum(j=0..(n-1)/3, C(n-1-3*j,j)*C(2*n-3*j-2,n-1))/n, n>0, a(0)=0. - Vladimir Kruchinin, May 24 2011 MATHEMATICA CoefficientList[InverseSeries[Series[y - y^2 - y^5, {y, 0, 30}], x], x] PROG (Maxima) a(n):=sum(binomial(n-1-3*j, j)*binomial(2*n-3*j-2, n-1), j, 0, (n-1)/3)/n; \\ Vladimir Kruchinin, May 24 2011 (PARI) Vec(serreverse(x-x^2-x^5+O(x^66))) /* Joerg Arndt, May 24 2011 */ CROSSREFS Sequence in context: A149935 A149936 A189176 * A301832 A272460 A149937 Adjacent sequences:  A063018 A063019 A063020 * A063022 A063023 A063024 KEYWORD nonn,easy AUTHOR Olivier Gérard, Jul 05 2001 STATUS approved

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Last modified December 8 12:31 EST 2019. Contains 329864 sequences. (Running on oeis4.)