OFFSET
0,4
FORMULA
E.g.f.: 1/(1 + LambertW(-x)) - x*(x + 1)*exp(x), where LambertW() is the Lambert W-function. - Ilya Gutkovskiy, Feb 08 2017
EXAMPLE
a(2) = 2^2 - 2^2 = 4 - 4 = 0.
a(3) = 3^3 - 3^2 = 27 - 9 = 18.
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Henry Bottomley, Nov 10 2000
STATUS
approved