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 A371370 #12 Sep 10 2024 06:17:26 %S A371370 0,1,5,62,1246,34734,1239708,53958456,2771832656,164151829440, %T A371370 11010949643640,825134834757936,68321156113803360,6194283782068848816, %U A371370 610322188305019432032,64936303681095948453120,7419917758371561069774336,906217650382400588573066880 %N A371370 E.g.f. satisfies A(x) = -log(1 - x/(1 - A(x))^2). %H A371370 <a href="/index/Res#revert">Index entries for reversions of series</a> %F A371370 E.g.f.: Series_Reversion( (1 - x)^2 * (1 - exp(-x)) ). %F A371370 a(n) = Sum_{k=1..n} (2*n+k-2)!/(2*n-1)! * |Stirling1(n,k)|. %F A371370 a(n) ~ LambertW(2*exp(3))^n * n^(n-1) / (sqrt(2*(1 + LambertW(2*exp(3)))) * (LambertW(2*exp(3)) - 2)^(3*n-1) * exp(n)). - _Vaclav Kotesovec_, Sep 10 2024 %t A371370 Table[Sum[(2*n+k-2)!/(2*n-1)! * Abs[StirlingS1[n,k]], {k,1,n}], {n,0,20}] (* _Vaclav Kotesovec_, Sep 10 2024 *) %o A371370 (PARI) my(N=20, x='x+O('x^N)); concat(0, Vec(serlaplace(serreverse((1-x)^2*(1-exp(-x)))))) %o A371370 (PARI) a(n) = sum(k=1, n, (2*n+k-2)!/(2*n-1)!*abs(stirling(n, k, 1))); %Y A371370 Cf. A368033, A371371. %Y A371370 Cf. A052842. %K A371370 nonn %O A371370 0,3 %A A371370 _Seiichi Manyama_, Mar 20 2024