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A375556
Expansion of e.g.f. 1 / (1 + x * log(1 - x^3/6)).
3
1, 0, 0, 0, 4, 0, 0, 70, 1120, 0, 5600, 184800, 2217600, 1201200, 61661600, 1513512000, 16682265600, 38118080000, 1440863424000, 31721866176000, 352561745536000, 2053230379200000, 68832104140800000, 1449890913639168000, 17583390443114496000
OFFSET
0,5
FORMULA
a(n) = n! * Sum_{k=0..floor(n/3)} (n-3*k)! * |Stirling1(k,n-3*k)|/(6^k*k!).
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1+x*log(1-x^3/6))))
(PARI) a(n) = n!*sum(k=0, n\3, (n-3*k)!*abs(stirling(k, n-3*k, 1))/(6^k*k!));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 19 2024
STATUS
approved