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#1 2005-12-21 11:51:47

John E. Franklin
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Registered: 2005-08-29
Posts: 3,588

Rubic's Cube solution

Does anyone know who came up with
the various solutions of the Rubik's
cube and how they went about
finding the moves that rotate the
corners without much disturbance
of rest of cube, etc?


igloo myrtilles fourmis

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#2 2005-12-21 12:04:18

mathsyperson
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Registered: 2005-06-22
Posts: 4,900

Re: Rubic's Cube solution

I have no idea who found it out or how they did it, but I can tell you the sequence of moves to rotate corners and stuff. I have a Rubik's book lying around somewhere.


Why did the vector cross the road?
It wanted to be normal.

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#3 2005-12-21 16:10:51

Jai Ganesh
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Registered: 2005-06-28
Posts: 45,954

Re: Rubic's Cube solution

I too got a book on how to solve it.
Here's a link to the official rubik's onine.


It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#4 2005-12-23 09:27:14

krassi_holmz
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Registered: 2005-12-02
Posts: 1,905

Re: Rubic's Cube solution

At last summer vacantion I've solved this game for a week. I haven't got any books about rubik cube. My strategy truely isn't the best, but it solves RK for about 5 minutes.


IPBLE:  Increasing Performance By Lowering Expectations.

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#5 2005-12-23 15:23:31

John E. Franklin
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Registered: 2005-08-29
Posts: 3,588

Re: Rubic's Cube solution

What is krassi_holmz saying.  I don't understand.
Did he solve the cube without learning some special moves??
When the rubik's cube first came out, I learned the solutions
and got pretty good at it.  But that was quite some time ago,
like around 1980.  I have a Rubik's cube now, and I relearned
the moves about a year ago and have again forgotten them,
but mostly I wondered if someone had some special math
up their sleeves when they figured out those amazing moves?
One move is called the rubik's manuever, so probably Erno Rubik
figured that one out himself, just guessing.


igloo myrtilles fourmis

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#6 2005-12-23 18:05:28

MathsIsFun
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Registered: 2005-01-21
Posts: 7,711

Re: Rubic's Cube solution

Yep, I think krassi got it all by himself ... gosh.

I got two levels, but kept on messing up on the third, so had to go buy the darned book.

The center is a fixed 3D cross, so you could write down the transformations in relation to it.

(And did you know those colors are just stuck on? When there is no other way ... )


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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#7 2005-12-26 10:39:07

krassi_holmz
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Registered: 2005-12-02
Posts: 1,905

Re: Rubic's Cube solution

The third level is truely the worst. I've got 4 operations and very unlike logic for solving it. And first I wanted to solve it by mathematical way. You can form a matrc transformations and matric equations but it goes bery slow.


IPBLE:  Increasing Performance By Lowering Expectations.

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#8 2005-12-26 11:08:01

mathsyperson
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Registered: 2005-06-22
Posts: 4,900

Re: Rubic's Cube solution

The third level isn't that hard, you just have to sort that one out before you look at the others. tongue


Why did the vector cross the road?
It wanted to be normal.

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#9 2005-12-28 11:22:07

John E. Franklin
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Registered: 2005-08-29
Posts: 3,588

Re: Rubic's Cube solution

I think anyone that can solve it without learning the solution tricks has got to be a genius!  Even learning the moves and when to apply them requires some aptitude, which I was able to handle.


igloo myrtilles fourmis

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#10 2005-12-29 01:18:14

krassi_holmz
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Registered: 2005-12-02
Posts: 1,905

Re: Rubic's Cube solution

It's just a matter of chance.
You make an operation. Then you determine how will it change all and if it's useful or useless.


IPBLE:  Increasing Performance By Lowering Expectations.

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#11 2006-06-09 15:24:47

John E. Franklin
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Registered: 2005-08-29
Posts: 3,588

Re: Rubic's Cube solution

Just found this virtual rubik's cube!!
http://www.rubiks.com/cube_online.html


igloo myrtilles fourmis

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#12 2007-06-20 15:48:35

mikau
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Registered: 2005-08-22
Posts: 1,504

Re: Rubic's Cube solution

Hey, guys! I finally figured out a way to solve the rubiks cube, and I didn't use the book either! big_smile
Was working on it about two or three days.

Now I've got to solve it again to proove it wasn't a fluke. Wish me luck! smile


A logarithm is just a misspelled algorithm.

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#13 2007-06-20 21:35:51

JaneFairfax
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Registered: 2007-02-23
Posts: 6,868

Re: Rubic's Cube solution

John E. Franklin wrote:

Just found this virtual rubik's cube!!
http://www.rubiks.com/cube_online.html

That virtual Rubik is fantastic!! up It’s so much better than this one in our own backyard: http://www.mathsisfun.com/games/rubiks-cube-puzzle.html tongue

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#14 2007-06-21 02:47:57

shocamefromebay
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Registered: 2007-05-30
Posts: 103

Re: Rubic's Cube solution

i solved it by myself once
i like discovered/made up my own kinda way to do it
i first solved the four corners of the rubiks cube like it was a 2x2x2 cube
then i would just rotate the middle piece of every side using logic/trial and error to get the answer
i made sure not to get the corners  mixed up again so i would not go backwards in progress
and if there was an edge tath needed to move to a different side
i would turn a side then rotate the middpiece taht it was on
and return the side piece taht i turned back to its original place to make sure not to mess up the corners
i would turn the rest of the edges taht didnt need to move to a different side by just moveing the middle piece of that side
and the center pieces are very simple to solve

and i have yet to read a book on how to solve the cube!!!
w00t i feel special!!!

Last edited by shocamefromebay (2007-06-21 02:49:43)

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#15 2007-06-21 06:35:07

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: Rubic's Cube solution

Anyway, here’s somebody who can solve the cube in 1 minute 6 seconds.

http://uk.youtube.com/watch?v=3c6VP47aXVY dizzy

Last edited by JaneFairfax (2007-06-25 21:25:44)

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#16 2007-06-21 09:47:38

Zhylliolom
Real Member
Registered: 2005-09-05
Posts: 412

Re: Rubic's Cube solution

Oh come on who uses both of their hands, this is where it's at

http://www.youtube.com/watch?v=vnRJROskpp4

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#17 2007-06-22 04:31:11

mikau
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Registered: 2005-08-22
Posts: 1,504

Re: Rubic's Cube solution

well i've done it about 8 more times using my own method. It takes me about 15 minutes average. I'm trying to get it down to 5 or at most 10.


A logarithm is just a misspelled algorithm.

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#18 2007-06-22 05:23:02

mathsyperson
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Registered: 2005-06-22
Posts: 4,900

Re: Rubic's Cube solution

Oh come on who uses both of their eyes, this is where it's at

http://www.youtube.com/watch?v=XBWDDCe7ChA


Why did the vector cross the road?
It wanted to be normal.

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#19 2007-06-22 06:09:32

Laterally Speaking
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Registered: 2007-05-21
Posts: 356

Re: Rubic's Cube solution

What would really be amazing is someone who can do it blindfolded with one hand.


"Knowledge is directly proportional to the amount of equipment ruined."
"This woman painted a picture of me; she was clearly a psychopath"

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#20 2007-06-22 06:25:44

Laterally Speaking
Real Member
Registered: 2007-05-21
Posts: 356

Re: Rubic's Cube solution

http://www.youtube.com/watch?v=wX4kZ4DEfzs

This is one heck of a cheater. Try pausing the movie right before he moves the cube off-screen; it is not solved.

Of course, it probably wasn't supposed to be a serious attempt.

Last edited by Laterally Speaking (2007-06-22 06:27:23)


"Knowledge is directly proportional to the amount of equipment ruined."
"This woman painted a picture of me; she was clearly a psychopath"

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#21 2007-06-25 13:57:34

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

Re: Rubic's Cube solution

Recently I have been inventing some of my own moves by starting with a solved cube, and then making some reasonably repetitive moves, and stop when things start to come back together.
Then examine what has changed and see if I can incorporate that into solving a cube. So far I came up with a couple things of interest, but still have to rely on a few methods invented by others that came in directions my brother kept from decades ago.


igloo myrtilles fourmis

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#22 2007-06-27 04:41:06

mikau
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Registered: 2005-08-22
Posts: 1,504

Re: Rubic's Cube solution

well when I was doing it, J.E.F, I noticed that in a certain scenario, i could move the corners of one side into place using two different sequences. (which were pretty much mirrored versions of eachother). Then I realized I could take a solved portion, do sequence A backwards to get back into that 'either way works' scenario, and then use sequence B to put things back into place. Then I observed how the other blocks changed when doing that, and used it to my advantage! smile

But that was generally the case with the whole thing. Find a way to get a secluded solved region out of place, and then back in place using a different sequence. Then see how the rest of the cube changed, and manipulate it! big_smile

(edit) hey, I just solved the virtual rubiks cube using my own method. That thing is pretty cool, but the view controls can be a tad annoying. x_x

Last edited by mikau (2007-06-27 11:40:35)


A logarithm is just a misspelled algorithm.

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#23 2007-07-03 02:34:28

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

Re: Rubic's Cube solution

mikau, I am totally impressed that you have figured out enough sequences to solve the whole cube on your own, without any help, I still have to learn somemore of my own moves to get to that point, but by using the memorized moves, I am a good rubik's solver, quite fast.  I would be interested in learning new sequences that anyone has come up with, like any of your's, if you want to give them away and have the time to write a sequence down.  Feel free to make up a twisting notation, like twist top cw,
middle vertical up 2 clicks, etc.

A.)
I'll start off with one of my moves, that is just a variation of the Rubik's manuver.
This move toggles the state of four top edges on the cube:
1. middle-vertical-up-90-degrees, top-ccw-90-degrees
2. middle-vertical-up-90-degrees, top-ccw-90-degrees
3. middle-vertical-up-90-degrees, top-ccw-90-degrees
4. middle-vertical-up-90-degrees, top-ccw-90-degrees
5. middle-vertical-down-90, top-ccw-90
6. middle-vertical-down-90, top-ccw-90
7. middle-vertical-down-90, top-ccw-90
8. middle-vertical-down-90, top-ccw-90
That's all for that.   The actual Rubik's manuver combines 3 & 4 and 7 & 8 by turning the top 180 degrees, and Rubiks manuver only affects two edges on the top of the cube, not all four like the one I described above.

B.)
Here's another move I use now when solving that I made up.
It is very repetitive, uses twelve motions, and turns three corners and
also messes up many edges, so I use it to solve corners before I do
edges.  What I do is find three corners on one side that I want to twist
in their spots.  Then I flip the cube around to its back and perform this
move:
1. Right-side-down-90
2. And turn the entire cube ccw looking at front face.
Repeat 1 & 2 eleven more times.
That's all for that one.  It twists the corners on the back of cube, 3 of them,
in opposite direction to a move that I read about in 70's or 80's with the original cube.

Last edited by John E. Franklin (2007-07-03 02:51:49)


igloo myrtilles fourmis

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#24 2007-07-05 04:44:04

mikau
Member
Registered: 2005-08-22
Posts: 1,504

Re: Rubic's Cube solution

Well JEF, I'll try to write down some of my sequences. However, the method I came up with does not use the cross method. So I doubt its the fastest way (since the cross method seems to be everyone's favorite, though I don't know how it works)

My way, I get the four corners of one side in place first, then I use a sequence to get the corners of the other side so that all 8 corners are in place, then I get the top and bottom sides in place, then I use another sequence to get the remaining sides either in place, or on the side opposite the correct side, and one more simple sequence to solve. I'll give you some of the sequences later on today.


A logarithm is just a misspelled algorithm.

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#25 2007-07-05 07:32:48

mikau
Member
Registered: 2005-08-22
Posts: 1,504

Re: Rubic's Cube solution

Okay, JEF. I've been wanting to write out my solution in case I ever forget it so I'll write it out
here: http://www.freewebs.com/mikau16/rubikSolution.html so you can read it. Its a lot to write out so i'm doing it a little at a time. I'll let you know when its finished.

Last edited by mikau (2007-07-05 08:07:03)


A logarithm is just a misspelled algorithm.

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