75542domain: NAppears in sequencesn*10^6-1, n*10^6-3, n*10^6-7 and n*10^6-9 are all prime.at n=7A064980Quotients A134245(n)/A134244(n).at n=10A134246a(n) = number of primes of the form k^n - m^k where k > m > 0.at n=47A242113a(n) = Sum_{k=1..n} sigma_3(k) * floor(n/k).at n=21A356043