Devise a two-player game based on 3-coloring a tiling of kites and darts.
geometry/coloring/kites.and.darts.game New
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Problem
Devise a two-player game based on 3-coloring a tiling of kites and darts. [ Editor: problem statement reconstructed from the source, an HTML letter from Rick (Mabry, according to the file name) to Antreas describing such a game; the conjecture mentioned, attributed to "JHC" (presumably John H. Conway), is that all such tilings can be 3-colored. ]
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Hi Antreas, Here is a portion of the K&D that the kids and I start with. We play only within the boundary, but one could also expand the boundary dynamically as needed. (As I mentioned, we play on the computer by clicking colors with a mouse, so that is easy.) [ Editor: picture game1.gif, not preserved. ] Player 1 goes first (now THAT is original) by filling any available tile with one of 3 agreed upon colors. I'll use red, yellow and green. Player 1 goes first below with a red kite. Subsequent legal moves are to color only tiles that are edge-adjacent to those already colored, and never to color two adjacent tiles the same color. So the second move must be yellow or green on any of the 4 tiles adjacent to the first red kite. I'll let Player 2 take a green kite. Player 1 then has many choices, but chooses a yellow dart. So here are the first three moves: [ Editor: picture game2.gif, not preserved. ] Not very interesting so far. Notice though, that there is a kite adjacent only to the green and yellow tiles that can only be colored red. Maybe Player 2 will stumble near this trap --- you win if you create an uncolored tile that is surrounded by 3 different colors, thereby destroying the 3-coloring of the tiling. (Remember, JHC conjectures that all of these can be 3-colored.) Player 2 fills the "ace" --- a novice! But that is not a bad move. Player 1 tries to sucker his opponent and colors a green kite: [ Editor: picture game3.gif, not preserved. ] But Player 2 is not such a novice after all and traps Player 1 by coloring an adjacent red kite and claiming a dart (which is then colored blue --- it's easier for us to color our captures than to initial them): [ Editor: picture game4.gif, not preserved. ] At this point we could either say that Player 2 has won the game and begin again (which I like --- it is more "pure" a game), or continue, leaving the capture tiles on the board. When doing the latter, we have decided that after capturing a tile, the victor may move again, which occasionally results in a few consecutive captures. Also, we don't allow the captured tile to be considered "colored", so a play adjacent to a captured tile must also be adjacent to a colored tile. The former game is interesting despite appearing to be short. When I play with Katy (15), the games are sometimes long --- a few dozen or so moves. (She wins about 40%, I'd say!) With 10-year-old Patrick, we usually play the 2nd method. I am not particularly good at this sort of thing, but I still win about 90% with Patrick! I have yet to play with a mathematician! So does it make sense? This is the first time I have tried to explain it, and I haven't tried to give an indication of how subtle and pretty a game I have found it to be. But as I said, I have yet to really test it. Let me know what you think. Want to play a quick transcontinental game? -- Rick