A077797 Numbers k for which there exist k-digit palindromic wing primes (a.k.a. near-repdigit palindromic primes) of the general form r*(10^k - 1)/9 + (m-r)*10^floor(k/2) where k is the number of digits (an odd number > 1), r is the repeated digit, and m (different from r) is the middle digit.

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

Offset: 1

Author

Patrick De Geest, Nov 16 2002

Keywords

• nonn
• base

References

• C. Caldwell and H. Dubner, "Journal of Recreational Mathematics", Volume 28, No. 1, 1996-97, pp. 1-9.

Links

• P. De Geest, PWP's Sorted By Length

Crossrefs

Cf. A077775-A077798.

Extensions

Name edited by Jon E. Schoenfield, Nov 04 2018