A377692 - OEIS

%I #18 Nov 05 2024 03:12:18

%S 1,2,12,118,1634,29408,654040,17362056,536410200,18922946928,

%T 750902659200,33118793900784,1607673329621712,85192554602094912,

%U 4894219487974911552,303021216528999244416,20116223556200658052992,1425479651299747192856832,107400336067263661850548224

%N E.g.f. satisfies A(x) = (1 - log(1 - x) * A(x))^2.

%F E.g.f.: 4/(1 + sqrt(1 + 4*log(1-x)))^2.

%F E.g.f.: B(x)^2, where B(x) is the e.g.f. of A052803.

%F a(n) = 2 * Sum_{k=0..n} (2*k+1)!/(k+2)! * |Stirling1(n,k)|.

%o (PARI) a(n) = 2*sum(k=0, n, (2*k+1)!/(k+2)!*abs(stirling(n, k, 1)));

%Y Cf. A007840, A377693.

%Y Cf. A052803, A377445.

%K nonn

%O 0,2

%A _Seiichi Manyama_, Nov 04 2024