My MediaWiki help

Editar y dar formato a las páginas:

https://www.mediawiki.org/wiki/Help:Formatting

Display numbers in titles - Mostrar números en los títulos: http://serverfault.com/questions/248942/how-can-i-configure-mediawiki-to-display-numbers-in-titles

user PREFERENCES -> MISC -> check Auto-numbering of heading.

If you want to add it by default for all users add a line:

$wgDefaultUserOptions['numberheadings'] = 1;

O éstas:

$wgExtensionFunctions[] = 'wfNumberHeadings';
function wfNumberHeadings() {
    global $wgUser;
    $wgUser->setOption('numberheadings', true);
}

to your LocalSettings.php.