From Don.Woods@eng.sun.com Fri Apr 24 17:56:26 1992 Return-Path: Received: from Sun.COM by life.ai.mit.edu (4.1/AI-4.10) id AA27121; Fri, 24 Apr 92 17:56:26 EDT Received: from Eng.Sun.COM (zigzag-bb.Corp.Sun.COM) by Sun.COM (4.1/SMI-4.1) id AA27750; Fri, 24 Apr 92 14:56:15 PDT Received: from colossal.Eng.Sun.COM by Eng.Sun.COM (4.1/SMI-4.1) id AA24248; Fri, 24 Apr 92 14:56:17 PDT Received: by colossal.Eng.Sun.COM (4.1/SMI-4.1) id AA22010; Fri, 24 Apr 92 14:56:22 PDT Date: Fri, 24 Apr 92 14:56:22 PDT From: Don.Woods@eng.sun.com (Don Woods) Message-Id: <9204242156.AA22010@colossal.Eng.Sun.COM> To: ACW@riverside.scrc.symbolics.com Subject: Description of Rubik's Tangle Cc: Cube-Lovers@ai.mit.edu > From: Allan C. Wechsler > I hope I'm not wasting too many people's time, but... can you describe > the Rubik's Tangle puzzle for those of us who haven't seen it? Your > description was interesting, but I wonder about your statement that it > can't be solved without a computer. Perhaps you just didn't have the > right insight. I would love to hear an insight that makes this puzzle tractible in real time (hours rather than days) by hand. Here's a brief description of Tangle #1; as I said in my earlier posting, I don't know how the other 3 differ, though I'm pretty sure they each have the same number of tiles. Tangle #1 consists of 25 square tiles, each of which has four colored ropes crossing it in the following pattern. (Note: This may be mirror imaged, since I'm working from memory.) --------------------- | @ # | | @ # | |$$ @ # %%%%| | $ @ %#% | | $ @ %% # | | $ %@ # | | $ %% @@# | | %%% #@@ | |%%%% $ # @@@| | $ # | | $ # | --------------------- The connection marked with $ actually wanders around the tile a bit more, but the connectivity is as shown. The object is to place the tiles in a 5x5 array such that wherever two tiles touch the colors of the ropes match. In Tangle #1 each permutation of colors occurs once, with one permutation occurring twice. The box says that if you get all four Tangles, you can put them together to make a 10x10 array under the same color-matching constraints. -- Don.