Greatest k such that (k-th prime) < (4 times n-th prime).

Terms

a(0) =4a(1) =5a(2) =8a(3) =9a(4) =14a(5) =15a(6) =19a(7) =21a(8) =24a(9) =30a(10) =30a(11) =34a(12) =38a(13) =39a(14) =42a(15) =47a(16) =51a(17) =53a(18) =56a(19) =61a(20) =61a(21) =65a(22) =67a(23) =71a(24) =76a(25) =79a(26) =80a(27) =82a(28) =84a(29) =87