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Expansion of (1+18*x)^(1/3).
4

%I #22 Jan 30 2020 21:29:15

%S 1,6,-36,360,-4320,57024,-798336,11632896,-174493440,2675566080,

%T -41738830848,660232415232,-10563718643712,170644685783040,

%U -2779070597038080,45576757791424512,-752016503558504448,12474626706088132608,-207910445101468876800,3479764291698268569600

%N Expansion of (1+18*x)^(1/3).

%H Seiichi Manyama, <a href="/A108733/b108733.txt">Table of n, a(n) for n = 0..799</a>

%F G.f.: (1-18*x)^(1/3) = 1 + 6*x/(G(0)-6*x) where G(k)= k*(1-18*x) + 1+ 6*x + 6*x*(k+1)*(3*k+2)/G(k+1); (continued fraction). - _Sergei N. Gladkovskii_, Jul 06 2012

%F a(n) ~ -(-1)^n * 2^n * 3^(2*n-1) / (Gamma(2/3) * n^(4/3)). - _Vaclav Kotesovec_, Jun 16 2018

%F D-finite with recurrence: n*a(n) +6*(3*n-4)*a(n-1)=0. - _R. J. Mathar_, Jan 20 2020

%t CoefficientList[Series[(1 + 18 x)^(1/3), {x, 0, 30}], x] (* _Vincenzo Librandi_, Jan 21 2020 *)

%K sign

%O 0,2

%A _N. J. A. Sloane_, Jun 22 2005