Number of primes < prime(n)^2.

Terms

a(0) =2a(1) =4a(2) =9a(3) =15a(4) =30a(5) =39a(6) =61a(7) =72a(8) =99a(9) =146a(10) =162a(11) =219a(12) =263a(13) =283a(14) =329a(15) =409a(16) =487a(17) =519a(18) =609a(19) =675a(20) =705a(21) =811a(22) =886a(23) =1000a(24) =1163a(25) =1252a(26) =1294a(27) =1381a(28) =1423a(29) =1523