OFFSET
1,3
FORMULA
a(1)=0= a(2); a(n)= n^2*(n+1)^(n-3), n >= 3.
E.g.f. (3*W(-x)^2-2*W(-x)^3-3*x^2-8*x^3)/(12*x), W(x) principal branch of Lambert's function.
a(n)=A055864(n, 3).
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang Jun 20 2000
STATUS
approved