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

Terms

a(0) =67a(1) =607a(2) =6977a(3) =68897a(4) =69067a(5) =69997a(6) =79867a(7) =80677a(8) =88867a(9) =97967a(10) =609607a(11) =660067a(12) =669667a(13) =676987a(14) =678767a(15) =697687a(16) =707677a(17) =766867a(18) =777677a(19) =786697a(20) =866087a(21) =879667a(22) =880667a(23) =886987a(24) =899687a(25) =906707a(26) =909767a(27) =966997a(28) =990967a(29) =6069977