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%I #26 Sep 08 2022 08:45:45
%S 1,2,11,66,461,3448,27061,219702,1829851,15547142,134224361,
%T 1174119120,10383783641,92691197962,834047700091,7557110252538,
%U 68890745834341,631392034936040,5814520777199261,53776065007163886,499275423496447211
%N Chebyshev transform of A107841.
%H Fung Lam, <a href="/A160852/b160852.txt">Table of n, a(n) for n = 0..1000</a>
%F G.f.: (1+x-x^2-sqrt(1-10*x-x^2+10*x^3+x^4))/(6*x*(1-x^2)).
%F G.f.: 1/(1-2x-x^2-6x^2/(1-5x-x^2-6x^2/(1-5x-x^2-6x^2/(1-5-x^2-6x^2/(1-... (continued fraction).
%F a(n) = Sum_{k=0..floor(n/2)} C(n-k,k)*A107841(n-2*k).
%F Recurrence: (n+1)*a(n) = (n-5)*a(n-6) + 5*(2*n-7)*a(n-5) - (2*n-7)*a(n-4) - 20*(n-2)*a(n-3) + (2*n-1)*a(n-2) + 5*(2*n-1)*a(n-1). - _R. J. Mathar_, Jul 24 2012, simplified by _Fung Lam_, Jan 27 2014
%F a(n) ~ r*(r+10) * sqrt(10*r^3-2*r^2-30*r+4) / (12 * sqrt(Pi) * n^(3/2) * r^(n+1)), where r = 1 / (5/2 + sqrt(6) + 1/2*sqrt(53+20*sqrt(6))) = 0.100010105114224353... - _Vaclav Kotesovec_, Feb 27 2014
%t CoefficientList[Series[(1+x-x^2-Sqrt[1-10x-x^2+10x^3+x^4])/(6x(1-x^2)),{x,0,20}],x] (* _Harvey P. Dale_, Aug 12 2011 *)
%o (PARI) x='x+O('x^30); Vec((1+x-x^2-sqrt(1-10*x-x^2+10*x^3+x^4))/(6*x*(1-x^2))) \\ _G. C. Greubel_, Apr 30 2018
%o (Magma) m:=25; R<x>:=PowerSeriesRing(Rationals(), m); Coefficients(R!((1+x-x^2-Sqrt(1-10*x-x^2+10*x^3+x^4))/(6*x*(1-x^2)))) // _G. C. Greubel_, Apr 30 2018
%K easy,nonn
%O 0,2
%A _Paul Barry_, May 28 2009