For several years, logologists have been wrestling with the problem of finding an English word containing the four rarest letters JQXZ.
In this article, we consider a closely related problem. There are 3,276 different ways that three letters can be chosen from the alphabet with repetition allowed (i.e., each letter is replaced after drawing, so that it can be drawn more than once). For each possible combination of letters, can one discover a word which uses them?
Card, Leslie E. and Eckler, A. Ross
"Words Having Three Rare Letters,"
Word Ways: Vol. 5
, Article 14.
Available at: https://digitalcommons.butler.edu/wordways/vol5/iss3/14