Primes with maximal digit = 4.

Terms

a(0) =41a(1) =43a(2) =241a(3) =401a(4) =421a(5) =431a(6) =433a(7) =443a(8) =1423a(9) =1433a(10) =2141a(11) =2143a(12) =2243a(13) =2341a(14) =2411a(15) =2423a(16) =2441a(17) =3041a(18) =3343a(19) =3413a(20) =3433a(21) =4001a(22) =4003a(23) =4013a(24) =4021a(25) =4111a(26) =4133a(27) =4201a(28) =4211a(29) =4231