A370701 Expansion of e.g.f. exp(-x^3)/(1-x).
1, 1, 2, 0, 0, 0, 360, 2520, 20160, 120960, 1209600, 13305600, 179625600, 2335132800, 32691859200, 479480601600, 7671689625600, 130418723635200, 2356429211136000, 44772155011584000, 895443100231680000, 18794168013164544000, 413471696289619968000
Offset: 0
Programs
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PARI
my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(-x^3)/(1-x))) -
PARI
a(n) = n!*sum(k=0, n\3, (-1)^k/k!);
Formula
a(n) = n! * Sum_{k=0..floor(n/3)} (-1)^k/k!.