From ccw@eql.caltech.edu Fri Nov 1 19:10:26 1991 Return-Path: Received: from EQL.Caltech.Edu by life.ai.mit.edu (4.1/AI-4.10) id AA16260; Fri, 1 Nov 91 19:10:26 EST Date: Fri, 1 Nov 91 15:49:59 PST From: ccw@eql.caltech.edu (Chris Worrell) Message-Id: <911101154959.23403c64@EQL.Caltech.Edu> Subject: What is the smallest cube which has all possible types of pieces? To: cube-lovers@ai.mit.edu Some cube discussion has started in rec.games.misc. I am trying to re-direct it to rec.puzzles, or hopefully cube-lovers. This is a copy of what I posted to rec.games.misc and rec.puzzles. Message follows: ------------------------------------ Newsgroups: rec.games.misc, rec.puzzles Subject: Re: Rubik's Wonderful Madness Followups-to: rec.puzzles johnf@apollo.hp.com (John Francis) writes... > >The 5x5x5 cube is the largest "interesting" cube from a solvers viewpoint. >The corner cubelets of cubes of all sizes can be solved the same way. >Similarly with the edge-centre cubelets of odd-sized cubes, etc., etc. >The 5x5x5 does not actually require any new solving techniques (if you can >solve a 3x3x3 and a 4x4x4 you can solve a 5x5x5), but it is the smallest >cube that contains cubelets of all possible types. Actually the 7x7x7 has a type of piece that the 5x5x5 does not have. This is a "face" piece which is not on a main diagonal of the face, nor on the main horizontal or vertical. These pieces come in 2 flavors, right-handed and left-handed (but I am not sure which should be called which). ---------------------- |A |B |C |D | | | | The 2x2x2 has types A ---------------------- The 3x3x3 has types A, D, K | |E |F |G | | | | The 4x4x4 has types A, B(C), E(I) ---------------------- The 5x5x5 has types A, B(C), D, E(I), G(J), K | |H |I |J | | | | The 6x6x6 has types A, B, C, E, F, H, I ---------------------- The 7x7x7 has types A-K | | | |K | | | | ---------------------- B and C are distinct at size 6+, but the same | | | | | | | | sorts of procedures work on both. ---------------------- Similarly for E & I. | | | | | | | | Similarly for G & J. For odd sizes 7+. ---------------------- Similarly for H & F. These are related | | | | | | | | by mirror imaging. Not by slice renumbering, ---------------------- like the above. Types F & H only start appearing at size 6. There are 24 of each of these pieces, and a type F can not be mixed with a type H. Discussions about the Rubik's cube and related puzzles should probably be directed to rec.puzzles rather than rec.games.misc. There is also a mailing list for theses topics. cube-lovers@ai.mit.edu Send mail to cube-lovers-request@ai.mit.edu to be added. Some sites may also see this as a newsgroup mlist.cube-lovers. But do not post to this group.