OFFSET
0,3
LINKS
Eric Weisstein's World of Mathematics, Lambert W-Function.
FORMULA
a(n) = n! * Sum_{k=0..floor(n/2)} (n-2*k)^(n-k) / (2^k * k! * (n-2*k)!).
PROG
(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(1+lambertw(-x*exp(x^2/2)))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Apr 30 2023
STATUS
approved