This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A370055 #26 Feb 06 2025 12:34:24
%S A370055 1,3,24,330,6552,171360,5581440,218045520,9945936000,519177859200,
%T A370055 30535045632000,1998518736614400,144098325316915200,
%U A370055 11350405033583616000,969837188805041356800,89351761457237190912000,8830056426362263572480000,931769828125956695715840000
%N A370055 a(n) = 3*(3*n+2)!/(2*n+3)!.
%F A370055 E.g.f.: exp( Sum_{k>=1} binomial(3*k,k) * x^k/k ).
%F A370055 a(n) = 3*A076151(n+1) for n > 0.
%F A370055 a(n) = A000142(n)*A001764(n+1). - _Alois P. Heinz_, Feb 08 2024
%F A370055 From _Seiichi Manyama_, Aug 31 2024: (Start)
%F A370055 E.g.f. satisfies A(x) = 1/(1 - x*A(x)^(2/3))^3.
%F A370055 a(n) = 3 * Sum_{k=0..n} (2*n+3)^(k-1) * |Stirling1(n,k)|. (End)
%F A370055 E.g.f.: (1/x) * Series_Reversion( x/(1 + x)^3 ). - _Seiichi Manyama_, Feb 06 2025
%o A370055 (PARI) a(n) = 3*(3*n+2)!/(2*n+3)!;
%Y A370055 Cf. A001763, A370054.
%Y A370055 Cf. A065866, A370058.
%Y A370055 Cf. A076151.
%Y A370055 Cf. A000142, A001764.
%K A370055 nonn
%O A370055 0,2
%A A370055 _Seiichi Manyama_, Feb 08 2024