OFFSET
0,6
FORMULA
a(n) = Sum_{k=4..n} 3^(n-k) * binomial(k,4) * |Stirling1(n,k)|.
E.g.f.: f(x) * log(f(x))^4 / 24, where f(x) = 1/(1 - 3*x)^(1/3).
PROG
(PARI) a(n) = polcoef(prod(k=0, n-1, x+3*k+1), 4);
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Apr 20 2025
STATUS
approved
