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 A367134 #15 Nov 07 2023 11:00:05
%S A367134 1,1,7,97,2051,58681,2122695,92960001,4782826459,282821367001,
%T A367134 18901822316543,1409070858589153,115925274671836371,
%U A367134 10433564954705754681,1019782291631652745591,107570331041074850633473,12180277895590328004331019,1473587743517654702900335705
%N A367134 E.g.f. satisfies A(x) = 1/(2 - exp(x*A(x)^2)).
%F A367134 a(n) = (1/(2*n+1)!) * Sum_{k=0..n} (2*n+k)! * Stirling2(n,k).
%F A367134 a(n) ~ 2^(n-1) * LambertW(exp(1/2))^(2*n + 1) * n^(n-1) / (sqrt(1 + LambertW(exp(1/2))) * exp(n) * (2*LambertW(exp(1/2)) - 1)^(3*n + 1)). - _Vaclav Kotesovec_, Nov 07 2023
%t A367134 Table[1/(2*n+1)! * Sum[(2*n+k)! * StirlingS2[n,k], {k,0,n}], {n,0,20}] (* _Vaclav Kotesovec_, Nov 07 2023 *)
%o A367134 (PARI) a(n) = sum(k=0, n, (2*n+k)!*stirling(n, k, 2))/(2*n+1)!;
%Y A367134 Cf. A000670, A052894, A367135.
%Y A367134 Cf. A367136, A367138.
%K A367134 nonn
%O A367134 0,3
%A A367134 _Seiichi Manyama_, Nov 06 2023