OFFSET
1,4
LINKS
N. J. A. Sloane, Transforms
FORMULA
G.f. A(x) satisfies: A(x) = x + x^2 * (1 + A(A(x))). - Ilya Gutkovskiy, May 10 2019
MATHEMATICA
Nest[x + x^2 + x^2 (# /. x -> #) &, O[x], 20][[3]] (* Vladimir Reshetnikov, Aug 08 2019 *)
CROSSREFS
KEYWORD
nonn,eigen
AUTHOR
STATUS
approved