This is a belated note to say (1) that I discovered the resource function FindExactCover through this post, and I've been using it extensively since -- so thank you for making it available! (2) I've been exploring a new twist on A-Puzzle-A-Day. I'll be leading a workshop on it at the 2024 Bridges Conference next week in Richmond, VA. The paper associated with the workshop can be had here: https://archive.bridgesmathart.org/2024/bridges2024-587.html (Brad is credited for FindExactCover). (3) Finally, I'll be presenting this material online Aug 21, 2024 for the Celebration of Mind series of the Gathering 4 Gardner. Info here: https://www.gathering4gardner.org/com-2024-08-21/
