3497539601domain: NAppears in sequencesNumbers of the form n^2+1 that divide 4^n-1.at n=10A273999Primes p of the form k^2 + 1 that divide 4^k - 1.at n=6A274000Primes p of the form (q-1)^2+1 that are a divisor of 4^(q-1)-1 where q is prime.at n=4A274002