Would you like to play a game?

February 18, 2008 12:29 AM

Fun and games with mathematics and mathematical puzzles (e.g. heart basket, Rubik's Cube, Rubik's Magic, hypercubes, and more) in both English and (with yet more content in) German.
posted by Blazecock Pileon (6 comments total)

Oh this is great, I know a five year old who will go apeshit for the paper slitting/folding ideas - not as hard as origami, and cool in a different way. Thanks.
posted by Rumple at 1:11 AM on February 18, 2008

Solving Rubik's cube is interesting, but the mechanical challenge of making a sturdy 7x7x7 cube is a pretty good puzzle in its own right. Watching the guy solve it is kind of boring, but it's surprising it exists at all. Apparently there are still larger ones to come, too.
posted by Wolfdog at 2:06 AM on February 18, 2008

My favorite Rubik-style puzzle actually wasn't one of Rubik's, but the Nintendo Barrel - perhaps just because I had to search a long time to find one. It's sitting here on my desk (solved) right now. In some ways, as an illustration of algebra ideas, it's clearer than the cube. There are a couple of simple moves you can do that have a cycle structure consisting of just two cycles of relatively prime length, meaning (by the Chinese Remainder Theorem - gosh! is there anything it can't do?) that actually you can push either cycle through as many steps as you want while leaving everything else on the puzzle fixed. Of course, you can find the same kind of thing on the cube, and the zillions of other permutation puzzle, but it's splendidly easy to see the beads moving 'round in their 9- and 11-cycles on the barrel.

It's funny this site got linked today, because I was just looking at it myself yesterday. In the evening I wrote some Mathematica code to do calculations in the barrel group, and found two easy sequences I hadn't known about before: one really simple move that breaks up as two disjoint 8-cycles (which are laid out in a very simple way to visualize) and a number of different, short ways of achieving a 21-cycle.
posted by Wolfdog at 2:23 AM on February 18, 2008

I always thought Rubik's Magic was pretty cool, although it felt like it was going to break at any second. Rubiks clock was pretty easy as you could isolate the movement of individual clocks.
posted by jeblis at 9:07 AM on February 18, 2008

Yes, Rubik's magic was, I think, the most ingenious design from Rubik beside the orginal cube itself - the design of the puzzle is more puzzlingly magical than the solution of it. The orginal one (three rings on a black background) was pretty sturdy, as I recall (I don't know what happened to mine). The bigger "Master" version was much less so.
posted by Wolfdog at 9:14 AM on February 18, 2008

This is a rare cool math site that I have not come across before. Thanks.
posted by wittgenstein at 2:04 PM on February 18, 2008