1786054147domain: NAppears in sequencesFirst occurrence of run of primes congruent to 3 mod 4 of exactly length n.at n=21A055624Initial prime in first sequence of n primes congruent to 3 modulo 4.at n=20A057619Initial prime in first sequence of n primes congruent to 3 modulo 4.at n=21A057619