No Posts…..

hello, why cant i put in ‘post__not_in’ => $digit variable ? because then i do like this it shows nothing no post list … but when i write with hand like this: ‘post__not_in’ => array(964, 333, 222, ), it shows post ? has any solution ?

<?php $digit = "array(".$list.")";?>

<ul>
<?php
$args = array(
  'orderby' => 'date',
  'order' => 'DESC',
	'post_type' => 'post',
	'numberposts' => 10,
	'post__not_in' => $digit,
	'showposts' => 10
  );
    $recentPosts = new WP_Query($args);
?>
<?php while ($recentPosts->have_posts()) : $recentPosts->the_post(); ?>
    <li><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></li>
<?php endwhile; ?>
</ul>