From hazard@niksula.hut.fi Fri Oct 20 12:29:49 1995 Return-Path: Received: from nukkekoti.cs.hut.fi by life.ai.mit.edu (4.1/AI-4.10) for /com/archive/cube-lovers id AA27480; Fri, 20 Oct 95 12:29:49 EDT Received: from ummagumma.tky.hut.fi (hazard@ummagumma.tky.hut.fi [130.233.33.120]) by nukkekoti.cs.hut.fi (8.6.12/8.6.11) with SMTP id SAA01720 for ; Fri, 20 Oct 1995 18:29:45 +0200 Date: Fri, 20 Oct 1995 18:29:45 +0200 Message-Id: <199510201629.SAA01720@nukkekoti.cs.hut.fi> X-Sender: hazard@pop.niksula.cs.hut.fi X-Mailer: Windows Eudora Pro Version 2.1.2 Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit To: cube-lovers@ai.mit.edu From: Mikko Haapanen Subject: Re: Old question about 2 adj edges >>I want to ask if somebody can tell me how to flip 2 adj. edges (and nothing >After buying my first cube, it took me about a week to figure out how >The 4x4x4 was a little tougher. It took me about a week to figure out >how to solve everything except two edge cubies which were exchanged. >It took me about another year(!) to figure out how to exchange them. It took me about 6 years. That problem was a little background process in my brains. Then i went to the army. In the evenings i used to 'play' with 4x4x4 until one day. I noticed the same thing as you. 2 flipped edges can be solved by turning one inner slice 90 degrees. Since then i haven't discovered anythig new about this parity problem. That's why i asked if anyone could do it less than 39 turns. >What I didn't see originally was that there could be invisible >movement of the face centers to compensate for the "bad parity" of >the edges. I am very poor at solving the 4x4x4, but here is how I I have thought the center piece movements too. It must be very hard to see a parity from certers, even if they were marked (position and orientation). There are so many different 'right' positions too. This reminds me another old question: 3x3x3 are told to have about 4 trillion (or whatever) different positions. How many of these positions are 'solved cube' but with different centerpiece combinations? Once i had 3x3x3 with 6 different pictures (picture/side). Friends asked me to solve it. When i was completed, they laughed at me and pointed the bottom center piece, which was out of orientation (i can't remember how many of centers were out of order). >Finally, here is my question. On the 4x4x4, I get "bad parity" darn >near every time. Why isn't it 50-50 like the situation I have with I don't know, but i guess: 1/4 you get it right and 3/4 goes wrong. I think we must count that there are 2 inner slice states: right and wrong. There are also 2 outer slice states: right and wrong (2 corners at wrong position). It makes me think that 1/4. ------Mikko Haapanen------hazard@niksula.hut.fi--------- Jos tahto siirtää vuoren, niin tahdon siirtää tahdon Vuorta siirtämään, että vuoren sisään nään -P.Hanhiniemi --------------------------------------------------------