Print a fabonacci series in php

Fab Series...........................

$first = 0;
   $second = 1;
   $n = 27;

   $inc = 1;

   do{
      $inc++;
      $final = $first + $second;
      $first = $second;
      $second = $final;
      echo $final." ";
   }
   while ($inc < $n) ;