1917000domain: NAppears in sequencesNumbers with at least three 3s in their prime signature.at n=35A176359G.f. A(x) satisfies: x*A(x) + x^2*A(x)^2 = C(x)^2, where C(x) = x + C(x)^2 is a g.f. of the Catalan numbers (A000108).at n=13A273958