Primes having only {1, 2, 9} as digits.

Terms

a(0) =2a(1) =11a(2) =19a(3) =29a(4) =191a(5) =199a(6) =211a(7) =229a(8) =911a(9) =919a(10) =929a(11) =991a(12) =1129a(13) =1229a(14) =1291a(15) =1999a(16) =2111a(17) =2129a(18) =2221a(19) =2999a(20) =9199a(21) =9221a(22) =9929a(23) =11119a(24) =11299a(25) =12119a(26) =12211a(27) =12911a(28) =12919a(29) =19121