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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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Comments: ( You must be logged in to post comments.)
  Subject Author Date
re: Up this to D3?brianjn2009-01-29 23:37:15
Up this to D3?rod hines2009-01-13 11:59:55
re(5): here are the pairs - thx Charliebrianjn2009-01-12 22:41:08
re(4): here are the pairs - thx Charlierod hines2009-01-12 14:34:44
Something in commonGamer2009-01-11 21:50:10
re(3): here are the pairs - thx Charliebrianjn2009-01-11 21:46:49
re(2): here are the pairs - thx CharlieCharlie2009-01-11 12:14:13
re: here are the pairs - thx Charliebrianjn2009-01-11 06:41:25
Hints/Tipshere are the pairsCharlie2009-01-10 14:23:33
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