OFFSET
0,4
FORMULA
a(n) = Sum_{k=0..n} (-4)^(n-k) * (Product_{j=0..k-1} (-4*j+1)) * Stirling1(n,k).
a(n) ~ n! * 2^(2*n-2) / (log(n)^(3/4) * n) * (1 - 3*(gamma + 1)/(4*log(n))), where gamma is the Euler-Mascheroni constant A001620. - Vaclav Kotesovec, Mar 05 2022
MATHEMATICA
m = 18; Range[0, m]! * CoefficientList[Series[(1 - Log[1 - 4*x])^(1/4), {x, 0, m}], x] (* Amiram Eldar, Mar 05 2022 *)
PROG
(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace((1-log(1-4*x))^(1/4)))
(PARI) a(n) = sum(k=0, n, (-4)^(n-k)*prod(j=0, k-1, -4*j+1)*stirling(n, k, 1));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Mar 05 2022
STATUS
approved