1005856domain: NAppears in sequencesExpansion of (1-x)/(1+2*x+2*x^3).at n=16A078062G.f. A(x) satisfies A(x) = 1 + x * ((1 - x) / A(x))^2.at n=9A366434Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,0) = 0^n and T(n,k) = k * Sum_{r=0..n} binomial(n,r) * binomial(3*r+k,n)/(3*r+k) for k > 0.at n=63A378318