David Nacin, Rutgers Experimental Mathematics Seminar, December 8, 2016
See part 2 at vimeo.com/194929070
Abstract: In the blog bit-player, Brian Hayes presented a KenKen puzzle over the complex numbers and stated that the uniqueness had not yet been checked. We present a proof of uniqueness and the classification of all four-by-four puzzles with unique solutions over all possible cage patterns. This result was originally done entirely in Python. It also follows from the work we present here, which involves the interactions between group actions on the sets of all possible puzzles and the set of order four Latin squares.