a(n) = lcm{1,2,...,n+1} * Sum_{k=0..n}((-1)^(n-k)/n+1-k)*s(-(n-1),k,n) where s(l,m,n) are the generalized Stirling numbers of the first kind. - Sean A. Irvine, Nov 10 2013
CROSSREFS
With different signs, this is the leading diagonal of A260781.
The coefficients used in numerical integration are given by fractions with A002397 as the denominators.
A002401 is the corresponding sequence for the symmetric method of estimation.