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 A362702 #19 Feb 16 2025 08:34:05
%S A362702 1,0,2,6,60,500,6150,81522,1300376,23024808,459915210,10104914270,
%T A362702 243652575012,6378414900156,180405368976014,5478759958122570,
%U A362702 177868544365861680,6146407749811022672,225262698504062963346,8727083181657584963766
%N A362702 Expansion of e.g.f. 1/(1 + LambertW(-x^2 * exp(x))).
%H A362702 Seiichi Manyama, <a href="/A362702/b362702.txt">Table of n, a(n) for n = 0..401</a>
%H A362702 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LambertW-Function.html">Lambert W-Function</a>.
%F A362702 a(n) = n! * Sum_{k=0..floor(n/2)} k^(n-k) / (k! * (n-2*k)!).
%o A362702 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(1+lambertw(-x^2*exp(x)))))
%Y A362702 Cf. A072034, A362703.
%Y A362702 Cf. A216507, A362347.
%K A362702 nonn,easy
%O A362702 0,3
%A A362702 _Seiichi Manyama_, Apr 30 2023