A077797 Palindromic wing primes (a.k.a. near-repdigit palindromes) of the general form a*(10^m-1)/9 +/- b*10^[ m/2 ] exist for digit lengths a(n).

3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 35, 39, 41, 45, 47, 53, 59, 63, 65, 67, 73, 79, 81, 87, 91, 109, 117, 119, 123, 139, 155, 159, 171, 177, 181, 185, 189, 195, 209, 225, 231, 233, 237, 259, 321, 325, 337, 339, 355, 363, 371, 375, 397, 425, 453