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1, 3, 8, 35, 154, 756, 3828, 20163, 108680, 598026, 3342404, 18929092, 108374252, 626264700, 3647936160, 21396522915, 126262239570, 749087596620, 4465444206300, 26733390275130, 160663411399920, 968937572793060, 5862111195487560, 35569106862459300, 216395609659221564
Sum_{n>=0} a(n)/8^n = 8 - 2*sqrt(10). - Amiram Eldar, May 05 2023
a[n_] := LucasL[n+1] * CatalanNumber[n]; Array[a, 25, 0] (* Amiram Eldar, May 05 2023 *)
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n*(n+1)*a(n) -2*n*(2n-1)*a(n-1) -4*(2*n-1)*(2*n-3)*a(n-2)=0. - R. J. Mathar, Sep 11 2012
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G.f. satisfies: A(x) = (2+5*x) - (1+4*x)*A(x) + x*(5+2*x)*A(x)^2 - 4*x^2*A(x)^3 + x^3*A(x)^4.
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(PARI) {a(n)=(2*fibonacci(n)+fibonacci(n+21))*binomial(2*n, n)/(n+1)}
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