A curious problem may be stated very simply for those familiar with the language of mathematics. Consider the free group on the 26 letters of the alphabet, with transposals as relations; is the group Abelian?
Wren, Bernard E. M.
"An Abelian Alphabet?,"
Word Ways: Vol. 27
, Article 21.
Available at: http://digitalcommons.butler.edu/wordways/vol27/iss2/21