Primes p such that the greatest prime factor of 3*p+1 is at most 5.

Terms

a(0) =3a(1) =5a(2) =13a(3) =53a(4) =83a(5) =853a(6) =2083a(7) =3413a(8) =5333a(9) =85333a(10) =208333a(11) =218453a(12) =341333a(13) =3495253a(14) =5461333a(15) =8533333a(16) =13981013a(17) =83333333a(18) =853333333a(19) =22369621333a(20) =218453333333a(21) =341333333333