simplificar-incremento.php para https://pt.stackoverflow.com/q/411247/3635

simplificar-incremento.php

<?php
 $c = 0;
 $permitidos = array(1, 41, 81, 121, 161, 201, 241, 281);
 
 foreach ($all_itens->result() as item) {
    $c++;

    if (in_array($c, $permitidos)) {
?>
    <div class='col'>
        <?=$item->id;?>
    </div>
<?php
    }
}