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 A384300 #11 May 26 2025 05:20:23
%S A384300 1,2,840,665280,980179200,2346549004800,8326896754176000,
%T A384300 41098950018846720000,269397128065642536960000,
%U A384300 2264501147602213494374400000,23751156416080627455365283840000,304080322557324667642345606348800000,4667216066941750219330172809445376000000
%N A384300 a(n) = Product_{k=0..2*n-1} (3*n+k-2).
%F A384300 a(n) = RisingFactorial(3*n-2,2*n).
%F A384300 a(n) = (2*n)! * [x^(2*n)] 1/(1 - x)^(3*n-2).
%F A384300 a(n) = (2*n)! * binomial(5*n-3,2*n).
%F A384300 D-finite with recurrence 3*(3*n-4)*(3*n-5)*a(n) -5*(5*n-4)*(5*n-3)*(5*n-7)*(5*n-6)*a(n-1)=0. - _R. J. Mathar_, May 26 2025
%o A384300 (PARI) a(n) = (2*n)!*binomial(5*n-3, 2*n);
%Y A384300 Cf. A384301, A384302, A384303.
%Y A384300 Cf. A384262.
%K A384300 nonn,easy
%O A384300 0,2
%A A384300 _Seiichi Manyama_, May 25 2025