Primes having only {0, 4, 7, 9} as digits.

Terms

a(0) =7a(1) =47a(2) =79a(3) =97a(4) =409a(5) =449a(6) =479a(7) =499a(8) =709a(9) =797a(10) =907a(11) =947a(12) =977a(13) =997a(14) =4007a(15) =4049a(16) =4079a(17) =4099a(18) =4409a(19) =4447a(20) =4799a(21) =4909a(22) =4999a(23) =7079a(24) =7477a(25) =7499a(26) =7907a(27) =7949a(28) =9007a(29) =9049