Primes having only {1, 4, 9} as digits.

Terms

a(0) =11a(1) =19a(2) =41a(3) =149a(4) =191a(5) =199a(6) =419a(7) =449a(8) =491a(9) =499a(10) =911a(11) =919a(12) =941a(13) =991a(14) =1499a(15) =1949a(16) =1999a(17) =4111a(18) =4441a(19) =4919a(20) =4999a(21) =9199a(22) =9419a(23) =9491a(24) =9941a(25) =9949a(26) =11119a(27) =11149a(28) =11411a(29) =11491