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A367879
Expansion of e.g.f. 1/(1 + 3 * x * log(1-x)).
4
1, 0, 6, 9, 240, 1170, 25812, 244440, 5464512, 79579584, 1926411120, 37900930320, 1018338863616, 25047229315680, 752077828672128, 22027545026192160, 738063856107279360, 24935406131189352960, 927531711339595204608, 35370336293213512527360
OFFSET
0,3
FORMULA
a(0) = 1; a(n) = 3 * n! * Sum_{k=2..n} 1/(k-1) * a(n-k)/(n-k)!.
a(n) = n! * Sum_{k=0..floor(n/2)} 3^k * k! * |Stirling1(n-k,k)|/(n-k)!.
PROG
(PARI) a(n) = n!*sum(k=0, n\2, 3^k*k!*abs(stirling(n-k, k, 1))/(n-k)!);
CROSSREFS
Sequence in context: A375661 A375672 A367881 * A377689 A377691 A377686
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Dec 03 2023
STATUS
approved