a(n) = prevprime(n) + n.

Terms

a(0) =5a(1) =7a(2) =8a(3) =11a(4) =12a(5) =15a(6) =16a(7) =17a(8) =18a(9) =23a(10) =24a(11) =27a(12) =28a(13) =29a(14) =30a(15) =35a(16) =36a(17) =39a(18) =40a(19) =41a(20) =42a(21) =47a(22) =48a(23) =49a(24) =50a(25) =51a(26) =52a(27) =59a(28) =60a(29) =63