a(1)=5; for n>0, a(n+1)=a(n)+p-1, where p is the smallest prime divisor of (a(n))^2-4.

Terms

a(0) =5a(1) =7a(2) =9a(3) =15a(4) =27a(5) =31a(6) =33a(7) =37a(8) =39a(9) =75a(10) =81a(11) =159a(12) =165a(13) =327a(14) =331a(15) =333a(16) =337a(17) =339a(18) =349a(19) =351a(20) =699a(21) =715a(22) =717a(23) =721a(24) =723a(25) =727a(26) =729a(27) =745a(28) =747a(29) =751