A380018 Expansion of e.g.f. 1/(exp(-4*x) - 4*x)^(1/4).
1, 2, 16, 256, 5856, 175296, 6486016, 285756416, 14606007296, 849615763456, 55415153442816, 4005309938466816, 317750919017168896, 27449350209163821056, 2564871898004949303296, 257753802183061443444736, 27720748513211258671988736, 3176821722223524679312736256
Offset: 0
Keywords
Programs
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PARI
a(n) = n!*sum(k=0, n, (-4)^k*(4*k+1)^(n-k)*binomial(-1/4, k)/(n-k)!);
Formula
a(n) = n! * Sum_{k=0..n} (-4)^k * (4*k+1)^(n-k) * binomial(-1/4,k)/(n-k)!.