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These problems deal with sequences of numbers. Can you spot what the sequences' rules are?
Difficulty: 2 of 5 Latest: Emirps census
An emirp (prime spelled backwards) is a prime number that results in a different prime when its decimal digits are reversed.
This definition excludes the related palindromic primes.

13, 17, 31, 37, 71... are emirps.


List values of q(n) (the number of emirps of length n) for n=2 to 6.

(No Solution Yet, 2 Comments) Submitted on 2018-10-12 by Ady TZIDON   
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