a(n) = smallest k such that Sum_{i=1..k} log(p_i)/p_i >= n, where p_i is the i-th prime.

Terms

a(0) =3a(1) =8a(2) =19a(3) =43a(4) =100a(5) =236a(6) =562a(7) =1354a(8) =3300a(9) =8119a(10) =20136a(11) =50302a(12) =126451a(13) =319628a(14) =811829a(15) =2070790a(16) =5302162a(17) =13621745a(18) =35101258a(19) =90696900a(20) =234924747a(21) =609864582a(22) =1586430423a(23) =4134442382a(24) =10793331294a(25) =28221407514a(26) =73898377351