OFFSET
1,2
FORMULA
exp(Sum_{n>=1} a(n) * x^n / n) = g.f. of A101880.
a(n) ~ n * n! * (1 - 1/n^2 - 6/n^3 - 38/n^4 - 276/n^5 - 2354/n^6 - 23458/n^7 - 268991/n^8 - 3490842/n^9 - 50520252/n^10 - ...). - Vaclav Kotesovec, Jan 28 2020
MATHEMATICA
nmax = 21; CoefficientList[Series[Log[Sum[k! x^k/Product[1 - x^j, {j, 1, k}], {k, 0, nmax}]], {x, 0, nmax}], x] Range[0, nmax] // Rest
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jan 14 2020
STATUS
approved