Codice PHP:
$imglav = array(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24);


$i=0;
$x=0;
$k=0;
    while(
$k <= count($imglav)){ 
    
$i++;
    
$x++;
    echo 
$imglav[$k++];
          if(
$i==4)  {
              echo 
'
'
;
              
$i=0;              
          }
              
        if(
$x==12)  {
            echo 
"


"
;
            
$x=0;
        }

    } 
L'ho adattato cosi' per prova