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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. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

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

LINKS

Table of n, a(n) for n=1..59.

P. De Geest, PWP's Sorted By Length

CROSSREFS

Cf. A077775-A077798.

Sequence in context: A294748 A082453 A033041 * A033039 A322660 A161957

Adjacent sequences:  A077794 A077795 A077796 * A077798 A077799 A077800

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Nov 16 2002

EXTENSIONS

Name edited by Jon E. Schoenfield, Nov 04 2018

STATUS

approved

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Last modified December 5 16:21 EST 2019. Contains 329753 sequences. (Running on oeis4.)