Number of Ramanujan primes R_k such that 2^(n-1) < R_k <= 2^n.

Terms

a(0) =0a(1) =1a(2) =0a(3) =0a(4) =1a(5) =2a(6) =3a(7) =6a(8) =10a(9) =19a(10) =33a(11) =62a(12) =118a(13) =208a(14) =409a(15) =740a(16) =1418a(17) =2676a(18) =5043a(19) =9638a(20) =18248a(21) =34949a(22) =66752a(23) =127880a(24) =245489a(25) =472113a(26) =908302a(27) =1751624a(28) =3381546a(29) =6534616