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    Original Cubelovers mailing list online

    The original cubelovers mailing list, active from 1980 to 1999, has apparently lost one of its main locations (Michael Reid's home page). I have thus put up a copy of the archive at http://cube20.org/cubelovers/ to help ensure it does not disappear from the face of the earth. I've...
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    God's Algorithm out to 18q*: 368,071,526,203,620,348

    Almost exactly four years after 17q* was announced by Thomas Schuenemann, we have calculated the number of positions at a distance of exactly 18 in the quarter-turn metric. This is more than one in twenty positions. This number matches (mod 48) the count of distance-18 symmetric...
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    4x4x4 FMC (computer and human)

    We're live! Give it a shot, human or computer, your code or someone else's. Let's see what we can do. Two months, five positions. http://codercontest.com/toms-fmc-4x4x4/
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    Claude Shannon (father of Communication Theory) and his Rubik Cube Poem

    I have been reading "The Idea Factory: Bell Labs and the Great Age of American Innovation" which focuses on Claude Shannon for one of its chapters. We all know of Shannon and all of his contributions to science. What you may not know of (as I certainly did not) is his fascination with the...
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    Find distance-24 (QTM) or greater position?

    I will give $50 to the first distance-24 or greater QTM position that anyone finds, that is not in the set of 13,099 positions I'm already aware of. To let you test what positions I'm aware of, I've put a Perl script at http://tomas.rokicki.com/qtmdb.pl.txt that you can run with a...
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    Fun flash puzzle

    If you haven't seen this you might take a look: http://olympic-cubes.com/ I've spent some time doing some analysis of this puzzle, but I'm going to hold off posting anything so as not to spoil it in any way. I would not be surprised if some of our colleagues here on this forum won't...
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    Three Million Randomly Selected Positions, Optimally Solved

    Using the Mersenne Twister pseudorandom number generator, I picked out three million cube positions. I then optimally solved each of these in both the quarter turn metric and half turn metric. From this data, I was able to calculate an approximate distance distribution, along with...
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    Gifts

    If you're not allowed to cut the paper, what's the smallest piece of wrapping paper (by area) that you can use to wrap a standard Rubik's cube that is 57mm on a side?
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    Lots of new results

    For those interested in computer cubing, lots of new results have been announced by Thomas Scheunemann in cubelovers: http://cubezzz.homelinux.org/drupal/ He has finished calculating the number of positions at 16q* and 17q*, and also 14f* and he threatens to finish 15f*. Well worth...
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    Void cube diameter at least 20 (probably 20)

    The void cube is the 3x3 without centers. For every legal 3x3 void position, there are 12 possible ways the centers can be inserted to yield a legal 3x3 cube position. (Pick any of the six colors for the top, then pick one of the adjacent four colors for the front; half of the time the result...
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    3x3x3 explored out to 12 in FTM

    I just finished exploring the 3x3x3 out to 12 face turns. Here are the statistics, first for positions with exactly that distance: d mod M + inv mod M positions -- ------------ ------------ -------------- 0 1 1 1 1 2...
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    29 QTM moves suffice

    While I was on vacation in San Diego, my computers notified me that they had completed sufficient cosets to prove that no Rubik's Cube position requires 30 or more quarter turns to solve. Thus, the upper bound on the QTM distance has been reduced to 29. A few more details are here...
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