上帝之数是20！已被证明！

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不小心看到Leyan Lo说的：网址：http://www.cube20.org/

粘点先：
Every position of Rubik's Cube™ can be solved in twenty moves or less.
With about 35 CPU-years of idle computer time donated by Google, a team of researchers has essentially solved every position of the Rubik's Cube™, and shown that no position requires more than twenty moves.

Every solver of the Cube uses an algorithm, which is a sequence of steps for solving the Cube. One algorithm might use a sequence of moves to solve the top face, then another sequence of moves to position the middle edges, and so on. There are many different algorithms, varying in complexity and number of moves required, but those that can be memorized by a mortal typically require more than forty moves.

One may suppose God would use a much more efficient algorithm, one that always uses the shortest sequence of moves; this is known as God's Algorithm. The number of moves this algorithm would take in the worst case is called God's Number. At long last, God's Number has been shown to be 20.

It took fifteen years after the introduction of the Cube to find the first position that provably requires twenty moves to solve; it is appropriate that fifteen years after that, we prove that twenty moves suffice for all positions……

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原帖由 dongjiangfeng 于 2010-8-9 11:29 发表 如果能把那个20步才能解开的about 300,000,000种情况的数据库公开，每次打乱都随机在里面选取，那就是绝对的公平了。

都隔这么长时间了，怎么还提这个……
而且，根本就不公平，比如那个superflip，只要还原所有楞块就好了……我感觉那最远状态里面一定有很多是“部分”已经完成了