Primes of the form XYYYYYYX, where Y is a single digit.

Terms

a(0) =1711111117a(1) =1766666617a(2) =2388888823a(3) =2399999923a(4) =2911111129a(5) =2933333329a(6) =2955555529a(7) =2966666629a(8) =2999999929a(9) =3188888831a(10) =4111111141a(11) =4133333341a(12) =4144444441a(13) =4188888841a(14) =4322222243a(15) =4333333343a(16) =4377777743a(17) =4388888843a(18) =4399999943a(19) =4744444447a(20) =4766666647