From: barnabyfinch@pe.net (Barnaby Finch)
Subject: Re: Rubik's cube
Date: Thu, 13 Jan 2000 21:37:51 GMT
Newsgroups: sci.math
Summary: [missing]
In article <85imsi$921$1@wanadoo.fr>, "Keyser Soze"
wrote:
> Hello everybody!!I'm a french studient, and i'm studying the most famous
> puzzle in the world: the Rubik's cube.
> I found some articles who were talking about groups, and number of
> solutions, optimization, matrix, etc... a lot of maths, and i would like to
> find more about it, i'd like to make a really good study... please help me
> find some results from scientists, so that i learn many many things. is
> there anyone who can help me? send me your answers to:
> bob.le.manouche@wanadoo.fr
> thanks to everyone
try:
http://web.usna.navy.mil/~wdj/rubik_nts.htm
http://web.idirect.com/~cubeman/index.html
or, peut etre, the old, unimpeachable source:
Notes on Rubik's Cube by David Singmaster
c'est tres magnifique!
Barnaby
==============================================================================
From: ishmnn@cap.bekkoame.or.jp (Ishihama Yoshiaki)
Subject: Re: Rubik's cube designs
Date: Sat, 15 Jan 2000 01:06:00 +0900
Newsgroups: rec.puzzles,alt.math,sci.math,alt.math.recreational,alt.brain.teasers,misc.writing,cz.soc.mensa
Summary: [missing]
In article <387DD6C1.24CC@ameritech.net>, hbizek@ameritech.net wrote:
> Hello, all,
> some of you will know me from previous postings. My quest for
> 3-dimensional Rubik's cobe designers is still a dismal zero. There is a
> real danger that I am the first to have come up with this. Please, if
> you know of anyone who does something similar to what I have done, let
> me know. The page to look at is http://cube.misto.cz. Please go down to
> the Appendices and click on "Thre-dimensional designs of Dr. Hana M.
> Bizek." Thank you.
3D Rubik cube is out of date, too old. Forget that.
Check my 4D rubik Cube applet please.
I also made 5D Rubik Cube simulations for Mac.
http://www.bekkoame.ne.jp/~ishmnn/java/java.html
--
Ishihama Yoshiaki
E-mail: ishmnn@cap.bekkoame.ne.jp
URL: http://www.asahi-net.or.jp/~hq8y-ishm/
==============================================================================
From: jmb184@frontiernet.net (John Bailey)
Subject: Re: Rubik's tour.
Date: Sat, 22 Jan 2000 13:14:55 GMT
Newsgroups: rec.puzzles,alt.math,sci.math,alt.math.recreational,alt.brain.teasers,misc.writing,cz.soc.mensa
Summary: [missing]
On Fri, 21 Jan 2000 23:39:24 GMT, "Androcles"
wrote:
>There is a well-known little puzzle known as the "Knight's Tour".
>The object of the puzzle is to have the (chess) knight visit all 64 squares
>on the chessboard
(snip)
>Suppose we have Rubik's cube, and suggest a tour such that all possible
>outcomes of the various configurations are presented. We begin with the
>identity.
>Question three, analogous to the knight's tour.
>How many configurations are there, each to be visited once and once only?
>Question four.
>Is this possible?
>Question five:
>How many moves does it take to return to the identity?
There may be other ways to interpret *tour* in the context of a Rubik
cube but this one is a lot of fun.
Using a Rubiks cube simulator with macro capability such as
http://www.mud.ca/cube/cube.html
enter a sequence of moves.
How many repetitions of these identical moves will return the cube to
its original state?
What sequence requires the most repetitions to restore?
John
==============================================================================
From: jmb184@frontiernet.net (John Bailey)
Subject: Re: Rubik's cube group
Date: Sat, 12 Aug 2000 12:11:17 GMT
Newsgroups: sci.math
Summary: [missing]
On Sat, 12 Aug 2000 07:00:06 GMT, kingjupiter@my-deja.com wrote:
>Has anyone looked into the group of permutations induced by the Rubik's
>cube (modulo the symetries of the cube.)
http://web.usna.navy.mil/~wdj/rubik_nts.htm
(quoting Dan Hoey)
Lecture notes on the mathematics of the Rubik's cube
Introduction
chapter 0 : Logic
chapter 1 : Functions on sets
chapter 2 : Permutations
chapter 3 : Permutation puzzles
part 1
part 2
part 3,
chapter 4 : Some solution strategies
chapter 5 : Groups, I
chapter 6 : Orbits, actions and cosets
chapter 7 : Cayley graphs and God's algorithm
chapter 8 : Symmetry groups of the Platonic solids
chapter 9 : Groups, II
chapter 10 : Structure of the Rubik's cube group
chapter 11 : Rubika esoterica
chapter 12 : Realizing PGL(2,F5) inside the Rubik's cube group
References
See also the Cube Lover's Archive, do a search within the document
using the key word group.
http://www.math.rwth-aachen.de/~Martin.Schoenert/Cube-Lovers/Index_by_Subject.html
John
==============================================================================
From: kingjupiter@my-deja.com
Subject: Re: Rubik's cube group
Date: Mon, 14 Aug 2000 02:29:06 GMT
Newsgroups: sci.math
Summary: [missing]
In article <8n7l3f$1e7$1@nnrp1.deja.com>,
kingjupiter@my-deja.com wrote:
> In article ,
> Fred W. Helenius wrote:
> > kingjupiter@my-deja.com wrote:
> >
> > >In article <8n4j3e$7q$1@nntp.Stanford.EDU>,
> > > theodore hwa wrote:
> > >> kingjupiter@my-deja.com wrote:
> >
> > >> : (fr)^63=1
> >
> > >> I believe it should be 105, not 63. (write out the cycle structure of
> > >> the permutation, or try it on an actual cube if you're really bored ;)
> >
> > >I did it twice. Both times I got 63.
> >
> > Are you sure you're not doing fr' or f'r (i.e., one of the turns
> > clockwise and the other counterclockwise)? Those motions have
> > period 63; fr (both turns clockwise) has period 105.
> >
>
> Yes, most likely, this is what I am doing...let me check...
>
> Yes, I am turning one clockwise and the other counterclockwise...
>
> Does anybody know what the order of this group is off the top of their
> heads?
Nevermind, I found it...
http://web.usna.navy.mil/~wdj/sm485_11.txt
The above link has lots of cool info about this group.
Thanks everyone for the info. I wonder if the Rubiks cube would be a
good teaching device for an basic group theory class? Or maybe
the "baby" Rubiks cube?
[multiple sigs deleted --djr]
==============================================================================
From: MattCAnderson1@juno.com
Subject: Re: Rubik's cube group
Date: Tue, 15 Aug 2000 06:57:00 GMT
Newsgroups: sci.math
In article <8n2sll$umt$1@nnrp1.deja.com>,
kingjupiter@my-deja.com wrote:
> Has anyone looked into the group of permutations induced by the Rubik's
> cube (modulo the symetries of the cube.)
>
> It seems to have 6 generators
>
> f (front)
> b (back)
> l (left)
> r (right)
> u (upper)
> d (downside) (I didn't want to use b or l again.)
>
> and relations
>
> fb=bf (this three relations come from turning non-incident faces)
> lr=rl
> ud=du
> (fr)^63=1
> (and 11 more relations of this form for each pair of incident faces.)
>
> What other relations do I need in order to pin down the Rubik's cube
> group? How many elements are in this group?
>
> THanks for any info.
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.
>
Hi,
I have a copy of 'Notes on Rubik's Magic Cube' by David Singmaster. I
will quote some things from it:
The number of different patterns is:
N=(2^27)*(3^14)*(5^3)*(7^2)*11
N is about 4.3 * 10^19
a little notation:
L-1 means move L face the other direction
L2 means move L face twice.
It is possible to generate the entire group with only 5 of the 6
moves. One way to do this is:
Let A = RL-1F2B2RL-1
then AUA = D.
So you can get the effect of moving the downside, without actually
doing so.
"Frank Barnes observes that the group of the cube is generated by two
moves:
alpha = L2BRD-1L-1
beta = UFRUR-1U-1F-1
Observe that alpha^7 is an 11-cycle of edges and alpha^11 is a 7-cycle
of corners"
It is a nice little book and has lots of results about Rubik's Cube.
Matt
Sent via Deja.com http://www.deja.com/
Before you buy.
==============================================================================
From: ajw01@uow.edu.au (Andrew John Walker)
Subject: Re: looking for "Cube Solver" Windows program
Date: 14 Aug 2000 16:14:32 +1000
Newsgroups: sci.math
Summary: [missing]
midi-man writes:
>Before I reformatted my harddrive, I had a Windows program called
>"Cube Solver" written by a man in Germany for solving the Rubik's.
>Does anyone have the URL for his page. It was a great little program,
>and it could search for patterns too. Thanks.
http://home.t-online.de/home/Kociemba/cube.htm
Andrew
==============================================================================
From: daniel_mcl@hotmail.com (Daniel McLaury)
Subject: Re: cube solver
Date: 15 Aug 2000 00:22:23 -0400
Newsgroups: sci.math
This page has instructions for solving one; you can write your
own program, if you know how. The directions are quite simple,
in fact, and it also has directions for cubes with sides of
2, 4, and 5!
http://www.unc.edu/~monroem/rubik.html
==============================================================================
From: jmb184@frontiernet.net (John Bailey)
Subject: Re: cube solver
Date: Tue, 15 Aug 2000 11:28:57 GMT
Newsgroups: sci.math
On 15 Aug 2000 00:22:23 -0400, daniel_mcl@hotmail.com (Daniel McLaury)
wrote:
>This page has instructions for solving one; you can write your
>own program, if you know how. The directions are quite simple,
>in fact, and it also has directions for cubes with sides of
>2, 4, and 5!
>
>http://www.unc.edu/~monroem/rubik.html
Nice site. To be complete you could add
http://www.frontiernet.net/~jmb184/interests/puzzles/4Cube/solution/
for a solution to the 2x2x2x2 (four dimensional cube)
John