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 A362339 #14 Feb 16 2025 08:34:05
%S A362339 1,1,1,1,-23,-119,-359,-839,78961,722737,3623761,13297681,-2115602279,
%T A362339 -27917827079,-195909017303,-980236890359,219254440161121,
%U A362339 3780662914771681,34105981790126881,216149350680413857,-62275804867272039479,-1325952502191492278039
%N A362339 a(n) = n! * Sum_{k=0..floor(n/4)} (-k)^k / (k! * (n-4*k)!).
%H A362339 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LambertW-Function.html">Lambert W-Function</a>.
%F A362339 E.g.f.: exp(x) / (1 + LambertW(x^4)).
%o A362339 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(x)/(1+lambertw(x^4))))
%Y A362339 Cf. A069856, A362337, A362338.
%Y A362339 Cf. A362349.
%K A362339 sign
%O A362339 0,5
%A A362339 _Seiichi Manyama_, Apr 17 2023