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A367884
Expansion of e.g.f. 1/(1 + x * log(1-3*x)).
1
1, 0, 6, 27, 432, 5670, 107892, 2245320, 55380672, 1525511232, 47089609200, 1600308206640, 59508149907456, 2400782506705440, 104471929620067968, 4876509369382166880, 243046385420037166080, 12881279635221755358720, 723372722620484975659008
OFFSET
0,3
FORMULA
a(0) = 1; a(n) = n! * Sum_{k=2..n} 3^(k-1)/(k-1) * a(n-k)/(n-k)!.
a(n) = n! * Sum_{k=0..floor(n/2)} 3^(n-k) * k! * |Stirling1(n-k,k)|/(n-k)!.
PROG
(PARI) a(n) = n!*sum(k=0, n\2, 3^(n-k)*k!*abs(stirling(n-k, k, 1))/(n-k)!);
CROSSREFS
Cf. A367883.
Sequence in context: A351735 A322233 A164985 * A048436 A276412 A006174
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Dec 04 2023
STATUS
approved