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 Mirror, mirror (Posted on 2012-05-04)
What palindromic prime number of n digits reads the same upside down or when viewed in a mirror?

Some examples for n=2 or 3:
11, 101, 181.

How far can you go?

Rem: Only digits 0,l and 8 qualify.

 No Solution Yet Submitted by Ady TZIDON Rating: 5.0000 (1 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
 A quick note and some Links (spoilers) | Comment 1 of 4
With the exception of 11, all such primes will have odd n because palindromes with an even number of digits are divisible by 11.

Here is a list of the first 22 such numbers
https://oeis.org/A068188

This site gives a very large number (n=180055)
http://mathworld.wolfram.com/TetradicNumber.html

 Posted by Jer on 2012-05-04 11:21:40
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