For your edification.

The first two prime numbers are 
2,3
after that , they can come in pairs,  that is
5,7
11,13
17,19
these pairs are called twin prime numbers
they are of the form
{p,p+2}
the list continues
23
is not part of a twin prime pair because of
divisibility by 5.  And 25 is not a prime number
27,29
is another twin pair
as the numbers get progressively bigger,
the prime numbers become less frequent,
because of all the small prime numbers.

Hopefully you learned something today.