OFFSET
0,2
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 0..110
FORMULA
a(k) ~ -3 * k! / (4 * (log(2))^(k+1)).
For n>0, a(n) = Sum_{k=1..n} A261239(k) * Stirling2(n-1, k-1).
EXAMPLE
A259472(n)/(-2*n!) ~ 1 - 3/n - 4/n^3 - 33/n^4 - 283/n^5 - 2785/n^6 - ...
MATHEMATICA
Flatten[{1, Table[Sum[CoefficientList[Assuming[Element[x, Reals], Series[E^(3/x)*x^3/ExpIntegralEi[1/x]^3, {x, 0, 25}]], x][[k+1]] * StirlingS2[n-1, k-1], {k, 1, n}], {n, 1, 20}]}]
CROSSREFS
KEYWORD
sign
AUTHOR
Vaclav Kotesovec, Aug 12 2015
STATUS
approved