How to include another php file after 6th post in home page

How to include another template file after 6th post in home page?

example
<?php include (TEMPLATEPATH . '/featured.php'); ?>

My home.php codes

<?php get_header(); ?>

	<div id="bigcolumn">
<?php include (TEMPLATEPATH . '/featured.php'); ?>
<?php
   if (is_home()) {
      query_posts($query_string . "&cat=-1");
   }
?>
	<?php if (have_posts()) : ?>

<div class="page-all">
	<div class="page-top">
	<div class="containerI">

<?php while (have_posts()) : the_post(); $loopcounter++; ?>
	<div id="post-<?php the_ID(); ?>" class="post item">
	<h1><a href="<?php the_permalink(); ?>" rel="bookmark" title="<?php the_title(); ?>"><?php the_title(); ?></a></h1>
	<div class="postinfo"><?php print WRITTEN; ?> <?php print ON_TEXT; ?> <?php the_time('j M, Y'); ?> <?php print AT_TEXT; ?> <?php the_time('G:i'); ?> <?php print IN_TEXT; ?> <b><?php the_category(', ') ?></b> | <?php print VIEWED; ?> <b><?php if(function_exists('the_views')) { the_views(); } ?></b> <?php print TIMES; ?> | <a href="<?php the_permalink(); ?>#comments"><b><?php comments_number(NO_COMMENTS,ONE_COMMENT,MORE_COMMENTS); ?></b></a> <?php edit_post_link(EDIT_ARTICLE, '', ''); ?></div>
	<div class="post-thumb"><?php show_thumb($options['GTwidth'],$options['GTheight'],$options['crop'],$options['quality']); ?></div>
	<p><?php print do_excerpt(get_the_excerpt(), 70); ?></p>
	<div class="clear"></div>
	</div>
<?php if ($loopcounter <= 1) { include (TEMPLATEPATH . '/random.php'); } ?>
		<?php endwhile; ?>
<div id="pagenavi">
	<!-- Plugin Navigation -->
<div class="tools">
	<?php if(function_exists('wp_pagenavi')) { wp_pagenavi(); } ?>
</div>
	<!-- End -->
</div>
	</div>
	</div>
	</div>

	<?php else : ?>

		<h2 class="center">Not Found</h2>
		<p class="center">Sorry, but you are looking for something that isn't here.</p>
		<?php get_search_form(); ?>

	<?php endif; ?>

	</div>

<?php get_sidebar(); ?>
<?php get_footer(); ?>