a(n) is the n-th prime == 1 (mod n).

Terms

a(0) =2a(1) =5a(2) =19a(3) =29a(4) =71a(5) =43a(6) =211a(7) =193a(8) =271a(9) =191a(10) =661a(11) =277a(12) =937a(13) =463a(14) =691a(15) =769a(16) =1531a(17) =613a(18) =2357a(19) =1021a(20) =1723a(21) =1409a(22) =3313a(23) =1609a(24) =3701a(25) =2029a(26) =3187a(27) =2437a(28) =6961a(29) =1741