22709274domain: NAppears in sequencesSmallest k such that k^2+1 is divisible by A002144(n)^4.at n=10A145297Largest number k such that the greatest prime factor of k^2+1 is A002313(n), the n-th prime not congruent to 3 mod 4.at n=11A185389a(n) is smallest number such that a(n)^2 + 1 is divisible by 97^n.at n=4A218719