A375609 Expansion of e.g.f. 1 / (exp(x^3) - x).
1, 1, 2, 0, -24, -240, -1800, -10080, -20160, 665280, 15120000, 219542400, 2335132800, 11416204800, -272432160000, -11126129414400, -252293974732800, -4099297608806400, -36217872365875200, 593695670606438400, 41572213064718336000, 1335024565711828992000
Offset: 0
Keywords
Programs
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PARI
my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(exp(x^3)-x))) -
PARI
a(n) = n!*sum(k=0, n\3, (-n+3*k-1)^k/k!);
Formula
a(n) = n! * Sum_{k=0..floor(n/3)} (-n+3*k-1)^k/k!.