Primes that contain digits 5 and 9 only.

Terms

a(0) =5a(1) =59a(2) =599a(3) =59999a(4) =95959a(5) =99559a(6) =599959a(7) =599999a(8) =995959a(9) =999599a(10) =999959a(11) =5595559a(12) =5595599a(13) =5599999a(14) =5955959a(15) =5995999a(16) =5999599a(17) =9555599a(18) =9559999a(19) =9595559a(20) =9955559a(21) =9995599a(22) =55555559a(23) =55559599a(24) =55595599a(25) =55599959a(26) =55959559a(27) =59999999a(28) =95559559