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%I #13 Apr 18 2023 08:28:24
%S 1,1,1,1,-23,-119,-359,-839,78961,722737,3623761,13297681,-2115602279,
%T -27917827079,-195909017303,-980236890359,219254440161121,
%U 3780662914771681,34105981790126881,216149350680413857,-62275804867272039479,-1325952502191492278039
%N a(n) = n! * Sum_{k=0..floor(n/4)} (-k)^k / (k! * (n-4*k)!).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LambertW-Function.html">Lambert W-Function</a>.
%F E.g.f.: exp(x) / (1 + LambertW(x^4)).
%o (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(x)/(1+lambertw(x^4))))
%Y Cf. A069856, A362337, A362338.
%Y Cf. A362349.
%K sign
%O 0,5
%A _Seiichi Manyama_, Apr 17 2023