Primes for which only two iterations of 'Prime plus its digit sum equals a prime' are possible.

Terms

a(0) =11a(1) =59a(2) =101a(3) =149a(4) =167a(5) =257a(6) =293a(7) =367a(8) =419a(9) =479a(10) =547a(11) =617a(12) =727a(13) =839a(14) =1409a(15) =1579a(16) =1847a(17) =2039a(18) =2129a(19) =2617a(20) =2657a(21) =2837a(22) =3449a(23) =3517a(24) =3539a(25) =3607a(26) =3719a(27) =4217a(28) =4637a(29) =4877