Greatest prime divisor of 2*prime(n)+1.

Terms

a(0) =5a(1) =7a(2) =11a(3) =5a(4) =23a(5) =3a(6) =7a(7) =13a(8) =47a(9) =59a(10) =7a(11) =5a(12) =83a(13) =29a(14) =19a(15) =107a(16) =17a(17) =41a(18) =5a(19) =13a(20) =7a(21) =53a(22) =167a(23) =179a(24) =13a(25) =29a(26) =23a(27) =43a(28) =73a(29) =227