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 A362480 #16 Feb 16 2025 08:34:05
%S A362480 1,1,-1,-17,-47,961,14191,-35825,-4258463,-46744703,1252890271,
%T A362480 49630926511,61171154353,-41944148256191,-1033550755723121,
%U A362480 24977027757497551,2117415434541888961,20487158235798909697,-3240242006475108681665,-146763820123398901335185
%N A362480 E.g.f. satisfies A(x) = exp(x - x^2 * A(x)^2).
%H A362480 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LambertW-Function.html">Lambert W-Function</a>.
%F A362480 E.g.f.: exp(x - LambertW(2*x^2 * exp(2*x))/2) = sqrt( LambertW(2*x^2 * exp(2*x))/(2*x^2) ).
%F A362480 a(n) = n! * Sum_{k=0..floor(n/2)} (-1)^k * (2*k+1)^(n-k-1) / (k! * (n-2*k)!).
%o A362480 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(exp(x-lambertw(2*x^2*exp(2*x))/2)))
%Y A362480 Cf. A362481, A362482.
%Y A362480 Cf. A143768, A362492.
%K A362480 sign
%O A362480 0,4
%A A362480 _Seiichi Manyama_, Apr 21 2023