Smallest prime p such that Sum_{primes q <= p} 1/q >= n/6.

Terms

a(0) =2a(1) =2a(2) =2a(3) =3a(4) =3a(5) =5a(6) =7a(7) =13a(8) =29a(9) =53a(10) =109a(11) =277a(12) =809a(13) =2741a(14) =11789a(15) =64663a(16) =483281a(17) =5195977a(18) =85861889a(19) =2358926351a(20) =118185163069