Finding Not-Quite-Prime Numbers Your challenge, should you chose to accept it, is to code-golf a function that returns true or false (or some similar meaningful representation of yes and no) if a number meets the following criteria:


The integer itself is a prime number OR
Either of its neighbor integers are prime


For example:
An input of 7 would return True.
An input of 8 would also return True.
An input of 15 would return False.  (Neither 14, 15, or 16 are prime)

The input must be able to return correctly for numbers between 2^0 and 2^20 inclusive, so there's no need to worry about sign issues or integer overflows.
J, 17

*/&lt;:$&amp;q:(&lt;:,],&gt;:)


Returns booleans encoded as process return codes: zero for true, nonzero for false.  Sample use:

   */&lt;:$&amp;q:(&lt;:,],&gt;:) 7
0
   */&lt;:$&amp;q:(&lt;:,],&gt;:) 8
0
   */&lt;:$&amp;q:(&lt;:,],&gt;:) 15
3