From cube-lovers-errors@mc.lcs.mit.edu Tue Sep 30 18:10:34 1997 Return-Path: Received: from sun30.aic.nrl.navy.mil by mc.lcs.mit.edu (8.8.1/mc) with SMTP id SAA21599; Tue, 30 Sep 1997 18:10:33 -0400 (EDT) Precedence: bulk Errors-To: cube-lovers-errors@mc.lcs.mit.edu Mail-from: From roger.broadie@iclweb.com Tue Sep 30 18:05:38 1997 From: roger.broadie@iclweb.com (Roger Broadie) To: Subject: Re: 4x4x4 solution Date: Tue, 30 Sep 1997 23:02:48 +0100 Message-Id: <19970930230037.AAA21244@home> C.McCaig@queens-belfast.ac.uk wrote: > ...I recently borrowed a friends 4x4x4, and I ... can't figure out a > move for reorientating the single edge pair.... It is possible to solve the problem with a sequence based on a quarter turn of a central slice, since that, like a swap of two edge pieces, involves an odd-parity cycle of the edge pieces. Thus r2 U2 r U2 r2 (where r is the turn of the inner slice next to R in the direction parallel to R) puts a 4-cycle of edges onto the top face, but leaves you with the task of restoring the centres. It was the desire to find something less cumbersome that first lead me to investigate the archives of this list, and there the answer was: Date: Fri, 20 Oct 95 12:46:32 -0400 (EDT) From: Georges Helm Subject: Re: Old question about 2 adj edges how to flip 2 adj. edges (and nothing else) in 4x4x4 cube? r^2 U^2 r l' U^2 r' U^2 r U^2 r l U^2 l' U^2 r U^2 l r^2 U^2 Georges geohelm@pt.lu It does indeed contain an odd number of turns of the central slices to give the desired parity. Roger Broadie