12748472domain: NAppears in sequencesa(n) = A142585(n) + A142586(n).at n=17A142710a(n) = ((sqrt(5) + 3)^n + (-sqrt(5) -1)^n + (-sqrt(5) + 3)^n + (sqrt(5) - 1)^n) / 2^n.at n=17A215500