Downloaded from Donald Knuth's [website](https://www-cs-faculty.stanford.edu/~knuth/programs.html):

> Datasets for exercises in The Art of Computer Programming:
> 
> [wordlists.tgz](https://www-cs-faculty.stanford.edu/~knuth/wordlists.tgz)
> - English words of lengths 2 thru 12 [OSPD4], ordered by frequency
