The 15 puzzle - solving the unsolvable 19th century Rubik's square

In this video the Mathologer has a close look at the granddaddy of all Rubik's "cubes", the puzzle that triggered the worldwide puzzle craze of 1880. Find out about how this puzzle managed to perplex millions of people, the mathematical Yin and Yang of permutations, and a set of false teeth.

Check out one of the Mathologer's old Rubik's cube public lectures from back in 2010 (with a guest appearance of Felix Zemdegs towards the end).
Also, check out THE definitive book about the 15 puzzle by Jerry Slocum and Sonneveld "The 15 Puzzle Book: How it Drove the World Crazy" http://www.amazon.com/The-15-Puzzle-Book-Drove/dp/1890980153 A few images in this video were grabbed from this book.

Enjoy!

Next episode

S02E04 - The dark side of the Mandelbrot set