later on vs than

later on

adv
  • At some time in the future; subsequently; later. 

than

adv
  • At that time; then. 

conj
  • Used in comparisons, to introduce the basis of comparison. 

prep
  • introduces a comparison, and is associated with comparatives, and with words such as more, less, and fewer. Typically, it seeks to measure the force of an adjective or similar description between two predicates. 

How often have the words later on and than occurred in a corpus of books? (source: Google Ngram Viewer )