What chapter of the Abhidharmartha Pradipika talks about infinite universes?
It is in ...

AN 3.80.
The Path of Purification, Six Recollection, Recollection into
Buddha's Value.(Visuddhimagga ChaAnussatiNiddesa
BuddhanussatiKatha).
AbhidhammatthaVibhavini 5th Chapter.
etc.

Abhidhanappadipika is a Glossary explanation.