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 A346433 #12 Jul 27 2021 06:56:31
%S A346433 1,2,14,142,1910,32094,647126,15223198,409276054,12378827166,
%T A346433 416006542550,15378483225758,620176642174742,27094392220198814,
%U A346433 1274759052849262422,64259896197635471006,3455259407744574799254,197401403111903906001310,11941074177046918285056470
%N A346433 E.g.f.: 1 / (2 - exp(2*(exp(x) - 1))).
%F A346433 a(0) = 1; a(n) = Sum_{k=1..n} binomial(n,k) * A001861(k) * a(n-k).
%F A346433 a(n) = Sum_{k=0..n} Stirling2(n,k) * 2^k * A000670(k).
%F A346433 a(n) ~ n! / (2*(2+log(2)) * (log(1+log(2)/2))^(n+1)). - _Vaclav Kotesovec_, Jul 27 2021
%t A346433 nmax = 18; CoefficientList[Series[1/(2 - Exp[2 (Exp[x]- 1)]), {x, 0, nmax}], x] Range[0, nmax]!
%t A346433 a[0] = 1; a[n_] := a[n] = Sum[Binomial[n, k] BellB[k, 2] a[n - k], {k, 1, n}]; Table[a[n], {n, 0, 18}]
%t A346433 Table[Sum[StirlingS2[n, k] 2^k HurwitzLerchPhi[1/2, -k, 0]/2, {k, 0, n}], {n, 0, 18}]
%o A346433 (PARI) my(x='x+O('x^25)); Vec(serlaplace(1 / (2 - exp(2*(exp(x) - 1))))) \\ _Michel Marcus_, Jul 18 2021
%Y A346433 Cf. A000670, A001861, A052555, A080253, A083355, A216794, A346417, A346432.
%K A346433 nonn
%O A346433 0,2
%A A346433 _Ilya Gutkovskiy_, Jul 17 2021