12556915219domain: NAppears in sequencesG.f. satisfies: A(x) = 1+x + x^2*A( (A(x)-1-x)/x ).at n=19A193296G.f. satisfies: A(x) = 1 / (1/x - 1 - A(A(x))), with A(0) = 0.at n=18A304454