118185163069domain: NAppears in sequencesa(n) is the smallest prime p such that Sum_{primes q <= p} 1/q >= n/2.at n=6A103592Smallest prime p such that Sum_{primes q <= p} 1/q >= n/4.at n=13A103596Smallest prime p such that Sum_{primes q <= p} 1/q >= n/6.at n=20A103600