Primes having only {0, 2, 4, 7} as digits.

Terms

a(0) =2a(1) =7a(2) =47a(3) =227a(4) =277a(5) =727a(6) =2027a(7) =2207a(8) =2447a(9) =2477a(10) =2707a(11) =2777a(12) =4007a(13) =4027a(14) =4447a(15) =7027a(16) =7207a(17) =7247a(18) =7477a(19) =7727a(20) =20047a(21) =20407a(22) =20477a(23) =20707a(24) =20747a(25) =22027a(26) =22247a(27) =22277a(28) =22447a(29) =22727