with -s and -en       (g) con -s      (h) con -en    (i) Nominative singular = plural     (only with neutral nouns) (only with masculine nouns) (only with masculine nouns) singular neutral masculine masculine   Nominative das Auto der Mensch der Onkel   Genitive des Autos des Menschen des Onkels   Dative dem Auto dem Menschen dem Onkel   Akkusativ das Auto den Menschen den Onkel   plural     Nominative die Autos die Menschen die Onkel   Genitive der Autos der Menschen der Onkel   Dative den Autos den Menschen den Onkeln   Akkusativ die Autos die Menschen die Onkel

As you can again see the articles are unchanged.
In the first example, there is the plural form unchanged in all the declinations which is quite logical since it would be hard to pronounce according to the rule that the Dative gets an additional n. Autosn is not even for Germans easy to pronounce.
The second example looks quite irregular. The ending -en is used in all the declinations - if the plural is formed with -en.
The third case is not too spectacular. The endings are the usual ones, only the plural form is actually the same like the singular one.

You see it is not impossible to do. Now we go on to more examples.