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~~~ Subject:

Morwen Thistlethwaite devised a solution for Rubik's cube which required at

most 50

turns. I would like to know where I can get a copy of this solution. Can

anyone help?

I have asked David Singmaster about this. He replied that he does have

Thistlethwaite's

solution, but that it has been significantly improved and he does not know

the details.

So, if someone can point me in the right direction I would be most grateful!

While I am interested in Thistlethwaite's solution, it is no use for speed

solving.

There was a recent posting, from Jiri Fridrich, which outlined his speed

solution, as

follows:

1. Do the four edges (white first) (2 sec.)

2. Put the white corner including the corresponding edge from the second

slice. When you put all four white corners, two slices on the cube will be

done. In this stage, almost no algorithms are necessary. Most positions

can be solved with intuition. (4 x 2 sec = 8 sec.)

3. Turn all 8 small cubes from the last slice so that the last face has

the same color. There are only 40 different positions (not counting

symmetrical positions). On average, 10 moves are necessary to do this

phase.(3 sec.).

4. Move the cubes in the last slice so that the cube is solved. There are

only 13 different positions. On average, 10-15 moves are necessary. (4

sec.)For the whole system, 40+13=53 algorithms are necessary. One also needs

about 8 short algorithms for the second phase. Altogether, 61 algorithms

will enable you to solve the cube in 17 seconds on average, if you can

turn 4 turns per second, and if you can minimize time gaps between

algorithms.

Is there any chance of Jiri Fridrich posting these algorithms (or perhaps making

them available via FTP)?

Thanks in advance...

Peter Foster

_______________________________________________________________ Peter Foster This sig is dedicated to all those who 616-231-2245 did not dedicate their sigs to themselves. pfoster@pcug.org.au