Primes having only {3, 5, 7} as digits.

Terms

a(0) =3a(1) =5a(2) =7a(3) =37a(4) =53a(5) =73a(6) =337a(7) =353a(8) =373a(9) =557a(10) =577a(11) =733a(12) =757a(13) =773a(14) =3373a(15) =3533a(16) =3557a(17) =3733a(18) =5333a(19) =5557a(20) =5573a(21) =5737a(22) =7333a(23) =7537a(24) =7573a(25) =7577a(26) =7753a(27) =7757a(28) =33353a(29) =33377