Code, script, functions to log out a user?

If I had a log out button that takes the user to a page that runs a script to log him out and then redirects him somewhere, how would the script in that page look like? Does it need a nonce?

ie:

<?php
/*
	Template Name: Sign Out
*/
wp_clear_auth_cookie();
echo "Signing you out, please wait...";
echo "<script type='text/javascript'>window.location = '".get_permalink(16)."?action=logout';</script>";
exit;
?>