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%I #17 Jan 20 2024 15:28:56
%S 1,3,-9,48,-288,1917,-13563,99927,-758079,5879754,-46401687,371336886,
%T -3005973612,24568135839,-202441986099,1679863711851,-14024710539684,
%U 117715876380531,-992724682487382,8407187391492162,-71467928398473984,609605247759545934,-5215842747304421544,44752623977413097928,-384969343166207926893
%N Expansion of (9*x^3+9*x+1)^(1/3).
%H Robert Israel, <a href="/A298308/b298308.txt">Table of n, a(n) for n = 0..1046</a>
%F G.f.: (9*x^3+9*x+1)^(1/3).
%F D-finite with recurrence: (-9+9*n)*a(n)+(15+9*n)*a(n+2)+(n+3)*a(n+3) = 0.
%F a(n) = Gamma(4/3)*Sum_{0<=j<=n/3} 9^(n-2*j)/(Gamma(4/3-n+2*j)*(n-3*j)!*j!).
%e (9*x^3+9*x+1)^(1/3) = 1+3*x-9*x^2+48*x^3-288*x^4+1917*x^5+...
%p f:= gfun:-rectoproc({(-9+9*n)*a(n)+(15+9*n)*a(n+2)+(n+3)*a(n+3), a(0) = 1, a(1) = 3, a(2) = -9},a(n),remember):
%p map(f, [$0..30]);
%t CoefficientList[Series[(9*x^3 + 9*x + 1)^(1/3), {x, 0, 25}], x] (* _Wesley Ivan Hurt_, Jan 20 2024 *)
%K sign
%O 0,2
%A _Robert Israel_, Jan 16 2018