Divisible only by primes congruent to 3 mod 5.

Terms

a(0) =1a(1) =3a(2) =9a(3) =13a(4) =23a(5) =27a(6) =39a(7) =43a(8) =53a(9) =69a(10) =73a(11) =81a(12) =83a(13) =103a(14) =113a(15) =117a(16) =129a(17) =159a(18) =163a(19) =169a(20) =173a(21) =193a(22) =207a(23) =219a(24) =223a(25) =233a(26) =243a(27) =249a(28) =263a(29) =283