585966domain: NAppears in sequencesG.f. A(x) satisfies: A(x)^2 - 2*A(x)^3 = -A(-x^2).at n=11A273320Signed recurrence over enriched r-trees: a(n) = (-1)^n + Sum_y Product_{i in y} a(y) where the sum is over all integer partitions of n - 1.at n=27A301470