1) Class of prime number
Found on
https://www.crosswordclues.com/clue/emirp
An emirp (prime spelled backwards) is a prime number that results in a different prime when its digits are reversed. This definition excludes the related palindromic primes. The term reversible prime may be used to mean the same as emirp, but may also, ambiguously, include the palindromic primes. The sequence of emirps begins 13, 17, 31, 37, 71, 7...
Found on
http://en.wikipedia.org/wiki/Emirp
A prime number that becomes a different prime number when its digits are reversed ('emirp' is 'prime' spelled backwards). The first twenty emirps are 13, 17, 31, 37, 71, 73, 79, 97, 107, 113, 149, 157, 167, 179, 199, 311, 337, 347, 359, and 389. Compare with a palindromic prime (see palindromic numb...
Found on
http://www.daviddarling.info/encyclopedia/E/emirp.html
No exact match found.
