Primes p such that p - d and p + d are also primes, where d is the largest digit of p.

Terms

a(0) =263a(1) =563a(2) =613a(3) =653a(4) =1613a(5) =1663a(6) =3463a(7) =4643a(8) =5563a(9) =5653a(10) =6263a(11) =6323a(12) =12653a(13) =13463a(14) =14633a(15) =16063a(16) =16223a(17) =21163a(18) =21563a(19) =25463a(20) =26113a(21) =30643a(22) =32063a(23) =33623a(24) =36313a(25) =41263a(26) =41603a(27) =44263a(28) =53623a(29) =54623