From:

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From: Allan C. Wechsler <ACW@riverside.scrc.symbolics.com>

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.