Program to find prime numbers in between a Range

<?php

error_reporting(E_ALL);

$num =23;

for( $j = 2; $j <= $num; $j++ )
{
for( $k = 2; $k < $j; $k++ )
{
if( $j % $k == 0 )
{
break;
}

}
if( $k == $j )
echo 'Prime Number : ', $j, ';
}

?>
<?php
function IsPrime($n)
{
 for($x=2; $x<$n; $x++)
   {
      if($n %$x ==0)
	      {
		   return 0;
		  }
    }
  return 1;
   }
$a = IsPrime(3);
if ($a==0)
echo 'This is not a Prime Number.....'."\n";
else
echo 'This is a Prime Number..'."\n";
?>