OFFSET
1,2
FORMULA
a(n) = n! * Sum_{k=1..n} (-1)^(k+1) * binomial(n-k+3,3) / k.
a(n) ~ log(2) * n^3 * n! / 6. - Vaclav Kotesovec, Aug 06 2021
MATHEMATICA
nmax = 21; CoefficientList[Series[Log[1 + x]/(1 - x)^4, {x, 0, nmax}], x] Range[0, nmax]! // Rest
Table[n! Sum[(-1)^(k + 1) Binomial[n - k + 3, 3]/k , {k, 1, n}], {n, 1, 21}]
PROG
(PARI) my(x='x+O('x^25)); Vec(serlaplace(log(1+x)/(1-x)^4)) \\ Michel Marcus, Aug 06 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Aug 05 2021
STATUS
approved