42693domain: NAppears in sequencesFloor-Sqrt transform of the numbers binomial(3*n,n)/(2*n+1) (A001764).at n=14A192665Numbers n such that sigma(n) = phi'(n), where sigma(n) is the sum of the divisors of n and phi'(n) is the arithmetic derivative of the Euler totient function of n.at n=5A261432