print checkboxes according to user defined value

I tried to print checkboxes according to number defined by the user,say user gave the input as 45 i want to print 45 checkboxes in 8 colums like 12345678 910111213141516

"; for($x=1;$x$x "; if($n%8==0){ echo '
'; }} echo '
'; echo""; echo""; ?>