fortuitously vs mistakenly

fortuitously

adv
  • In a fortuitous manner; in a manner of happening by chance; coincidentally; accidentally. 

  • In a fortuitous manner; in a manner of happening by a lucky chance; luckily; fortunately. 

mistakenly

adv
  • by accident, by mistake, in error (without intention to do so) 

  • wrongly, erroneously 

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