226617domain: NAppears in sequencesa(0) = 1; a(n) = 2*n*a(n-1) - 1 for n >= 1.at n=7A055214G.f. A(x) satisfies: 1 = A(x) - x/(A(x) - x*A(x)/(A(x) - x*A(x)^2/(A(x) - x*A(x)^3/(A(x) - x*A(x)^4/(A(x) ...))))), a continued fraction relation.at n=12A338747