invoke vs strike up

invoke

verb
  • To call to mind (something) for some purpose. 

  • To appeal for validation to a (notably cited) authority. 

  • To cause (a program or subroutine) to execute. 

  • To solicit, petition for, appeal to a favorable attitude. 

  • To conjure up with incantations. 

  • To bring about as an inevitable consequence. 

  • To call upon (a person, a god) for help, assistance or guidance. 

strike up

verb
  • To start something with somebody else, such as a conversation or relationship. 

  • To start something, usually playing live music. 

  • To raise (as sheet metal), in making dishes, pans, etc., by blows or pressure in a die. 

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