Click the image to reach the 10/1/08 post on This Side of the Pond explaining the contest. (Naturally, if it's much past October 1, 2008, you'll want to check whether there's a more recent entry...)
On the other hand, I had forgotten about hexahexaflexagons. I used to be able to make them in my sleep. Perhaps it is time for me to dust off that old skill.
On the other hand, I had forgotten about hexahexaflexagons. I used to be able to make them in my sleep. Perhaps it is time for me to dust off that old skill.