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 A277969 a(n) = Sum_{k=0..n} binomial(n-3,n-k)*Catalan(k). 1
 1, -1, 2, 5, 19, 75, 305, 1270, 5390, 23236, 101480, 448085, 1997115, 8973255, 40602093, 184853055, 846206025, 3892585325, 17984308775, 83417287855, 388297304825, 1813341109825, 8493372326675, 39889629750600, 187812852106636 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Robert Israel, Table of n, a(n) for n = 0..1430 FORMULA G.f.: ((1-x)^3*(1-sqrt((5*x-1)/(x-1))))/(2*x). a(n) ~ 8*5^(n-3/2) / (sqrt(Pi)*n^(3/2)). - Vaclav Kotesovec, Nov 07 2016 (5*n-10)*a(n)-(7+6*n)*a(n+1)+(n+3)*a(n+2)=0 for n >= 2. - Robert Israel, Nov 21 2016 a(n) = A055452(n+1) for n > 2. - Georg Fischer, Oct 23 2018 MAPLE f:= gfun:-rectoproc({(5*n-10)*a(n)+(-7-6*n)*a(n+1)+(n+3)*a(n+2), a(0) = 1, a(1) = -1, a(2) = 2, a(3) = 5}, a(n), remember): map(f, [\$0..30]); # Robert Israel, Nov 21 2016 MATHEMATICA CoefficientList[Series[((1 - x)^3 (1 - Sqrt[(5 x - 1) / (x - 1)])) / (2 x), {x, 0, 25}], x] (* Vincenzo Librandi, Nov 07 2016 *) PROG (Maxima) a(n):=sum((binomial(2*k, k)*binomial(n-3, n-k))/(k+1), k, 0, n); (PARI) x='x+O('x^50); Vec(((1-x)^3*(1-sqrt((5*x-1)/(x-1))))/(2*x)) \\ G. C. Greubel, Apr 09 2017 CROSSREFS Cf. A000108, A055452. Sequence in context: A255541 A150026 A150027 * A058131 A222055 A228569 Adjacent sequences:  A277966 A277967 A277968 * A277970 A277971 A277972 KEYWORD sign AUTHOR Vladimir Kruchinin, Nov 06 2016 STATUS approved

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Last modified November 29 02:45 EST 2020. Contains 338756 sequences. (Running on oeis4.)