Twin prime

A twin prime pair is a pair of prime numbers spaced apart by 2. A twin prime is a member of such a pair.

It is suspected that there exist infinitely many twin prime pairs, but this has never been proven.

Examples
The first ten pairs are:


 * 3 and 5
 * 5 and 7
 * 11 and 13
 * 17 and 19
 * 29 and 31
 * 41 and 43
 * 59 and 61
 * 71 and 73
 * 101 and 103
 * 107 and 109