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An Odd Couple (Posted on 2009-01-10) Difficulty: 2 of 5
There are 43 3-digit prime numbers which, when reversed, also yield a prime number. (Eight of these are actually consecutive primes).

Of the 43, 15 are simply palindromes (e.g. 929), but of the remaining 14 pairs of numbers (called 'emirp's), one pair in particular exhibits two unique characteristics, one of which is rather surprising.

What are the numbers, and what are their unique characteristics?

See The Solution Submitted by rod hines    
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re(2): here are the pairs - thx Charlie | Comment 3 of 9 |
(In reply to re: here are the pairs - thx Charlie by brianjn)

Only thing I can make out is that 733 and 337, when turned upside down in a calculator each makes a word, LEE and EEL. I don't know if that could be it.
  Posted by Charlie on 2009-01-11 12:14:13

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