280856domain: NAppears in sequencesG.f.: A(x) = A_1 where A_1 = 1/[1 - x*(A_2)^2], A_2 = 1/[1 - x^2*(A_3)^2], A_3 = 1/[1 - x^3*(A_4)^2], ... A_n = 1/[1 - x^n*(A_{n+1})^2] for n>=1.at n=19A132332G.f. A(x) satisfies: A(x) = 1/(1 - x*A(x)/(1 - x^2*A(x)^2/(1 - x^3*A(x)^3/(1 - x^4*A(x)^4/(1 - ...))))), a continued fraction.at n=11A301627