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 A064306 Convolution of A052701 (Catalan numbers multiplied by powers of 2) with powers of -1. 5
 1, 1, 7, 33, 191, 1153, 7295, 47617, 318463, 2170881, 15028223, 105365505, 746651647, 5339185153, 38478839807, 279201841153, 2037998419967, 14954803494913, 110255315877887, 816299567480833, 6066679566041087 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS G. C. Greubel, Table of n, a(n) for n = 0..1000 W. Lang, On polynomials related to derivatives of the generating function of Catalan numbers, Fib. Quart. 40,4 (2002) 299-313; Eq.(31) with lambda=-1/2. FORMULA a(n) = (-1)^n*Sum_{k=0,..,n} (C(k)/(-1/2)^k) with C(k)=A000108(k) (Catalan). a(n) = -a(n-1) + C(n)*2^n, n >= 0, a(-1) := 0, with C(n)=A000108(n). G.f.: A(2*x)/(1+x), with A(x) g.f. of Catalan numbers A000108. Recurrence: (n+1)*a(n) = (7*n-5)*a(n-1) + 4*(2*n-1)*a(n-2). - Vaclav Kotesovec, Dec 09 2013 a(n) ~ 2^(3*n+3)/(9*sqrt(Pi)*n^(3/2)). - Vaclav Kotesovec, Dec 09 2013 MATHEMATICA CoefficientList[Series[(1-Sqrt[1-8*x])/(4*x*(1+x)), {x, 0, 20}], x] (* Vaclav Kotesovec, Dec 09 2013 *) Table[FullSimplify[2^(n+1)*(2*n+2)! * Hypergeometric2F1Regularized[1, n+3/2, n+3, -8]/(n+1)! + (-1)^n/2], {n, 0, 20}] (* Vaclav Kotesovec, Dec 09 2013 *) Table[(-1)^n*Sum[(-2)^k * CatalanNumber[k], {k, 0, n}], {n, 0, 50}] (* G. C. Greubel, Jan 27 2017 *) PROG (Sage) def A064306():     f, c, n = 1, 1, 1     while True:         yield f         n += 1         c = c * (8*n - 12) // n         f = c - f a = A064306() print([next(a) for _ in range(21)]) # Peter Luschny, Nov 30 2016 (PARI) for(n=0, 25, print1((-1)^n*sum(k=0, n, (-2)^k*binomial(2*k, k)/(k+1)), ", ")) \\ G. C. Greubel, Jan 27 2017 CROSSREFS Sequence in context: A275860 A054256 A085636 * A292427 A333565 A215125 Adjacent sequences:  A064303 A064304 A064305 * A064307 A064308 A064309 KEYWORD nonn,easy AUTHOR Wolfdieter Lang, Sep 13 2001 STATUS approved

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Last modified August 5 06:46 EDT 2020. Contains 336209 sequences. (Running on oeis4.)