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 A367472 #9 Nov 19 2023 08:25:03
%S A367472 1,6,60,816,13992,289176,6990360,193432056,6028092312,208891033656,
%T A367472 7966989308760,331618933474296,14958464943057432,726825458489514936,
%U A367472 37846457287387667160,2102428978611587164536,124109778776508893651352,7758254465575303379273016
%N A367472 Expansion of e.g.f. 1 / (4 - 3 * exp(x))^2.
%F A367472 a(n) = Sum_{k=0..n} 3^k * (k+1)! * Stirling2(n,k).
%F A367472 a(0) = 1; a(n) = 3*Sum_{k=1..n} (k/n + 1) * binomial(n,k) * a(n-k).
%F A367472 a(0) = 1; a(n) = 6*a(n-1) - 4*Sum_{k=1..n-1} (-1)^k * binomial(n-1,k) * a(n-k).
%o A367472 (PARI) a(n) = sum(k=0, n, 3^k*(k+1)!*stirling(n, k, 2));
%Y A367472 Cf. A032033, A367473.
%Y A367472 Cf. A005649, A367470.
%K A367472 nonn
%O A367472 0,2
%A A367472 _Seiichi Manyama_, Nov 19 2023