indelible vs persisting

indelible

adj
  • Incapable of being canceled, lost, or forgotten. 

  • Having the quality of being difficult to delete, remove, wash away, blot out, or efface. 

  • Incapable of being annulled. 

persisting

noun
  • persistence 

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