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%I #18 Aug 21 2024 11:23:26
%S 1,-1,1,-1,2,-11,61,-281,1191,-5923,41791,-354091,2968021,-24059751,
%T 204718515,-1996937671,22125450621,-258434553861,3056858429581,
%U -37181421375349,482010195953821,-6741275765687821,99663246605243861,-1521712424934601901
%N Expansion of e.g.f. 1/(exp(x) - x^4/24).
%F a(n) = binomial(n,4) * a(n-4) - Sum_{k=1..n} binomial(n,k) * a(n-k) for n > 3.
%F a(n) ~ n! * 3*(-1)^n / ((1 + LambertW(3^(1/4) / 2^(5/4))) * 2^(2*n + 7) * LambertW(3^(1/4) / 2^(5/4))^(n+4)). - _Vaclav Kotesovec_, Mar 12 2022
%F a(n) = n! * Sum_{k=0..floor(n/4)} (-k-1)^(n-4*k)/(24^k*(n-4*k)!). - _Seiichi Manyama_, Aug 21 2024
%t m = 23; Range[0, m]! * CoefficientList[Series[1/(Exp[x] - x^4/24), {x, 0, m}], x] (* _Amiram Eldar_, Mar 12 2022 *)
%o (PARI) my(N=40, x='x+O('x^N)); Vec(serlaplace(1/(exp(x)-x^4/24)))
%o (PARI) b(n, m) = if(n==0, 1, sum(k=1, n, (-1+(k==m))*binomial(n, k)*b(n-k, m)));
%o a(n) = b(n, 4);
%Y Cf. A089148, A352309, A352310.
%Y Cf. A352304.
%K sign
%O 0,5
%A _Seiichi Manyama_, Mar 11 2022