1901198domain: NAppears in sequencesa(n) = 10*a(n-1) - a(n-2) with a(0) = 0, a(1) = 2.at n=7A001078Denominators of continued fraction convergents to sqrt(6).at n=13A041007Denominators of continued fraction convergents to sqrt(54).at n=13A041093Square root of floor(A055851(n)/6).at n=22A204519