Amazing move !!!

on a fully solved rubik's cube make the following move continuously 10 times

you will find that first the cube get scrambled at some parts then eventually it get solved

the move is : \( R U R' F \)

#Combinatorics #RubiksCube

Note by Rishabh Jain
6 years, 8 months ago

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Comments

Please explain it more!!!!!!

sameer jain - 6 years, 8 months ago

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DTYW CI6

Lester Nyroh Villanueva - 6 years, 8 months ago

there is nothing to explain just solve the rubik's cube and apply the given algorithm (it won't help you to solve the cube its just a magic move)

Rishabh Jain - 6 years, 8 months ago

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All algorithms when repeated enough times on a solved cube result in a completely solved cube. You can do any specific set of moves repeatedly without moving the cube and it'll get back together eventually.

Muhtasim Dibbo - 6 years, 8 months ago

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@Muhtasim Dibbo but can u tell me how number of moves affect the number of times that you should that move like just in my example its 10 times

Rishabh Jain - 6 years, 8 months ago

@Muhtasim Dibbo That's actually not how that works. Significant group theoretic work went into understanding the Hamiltonian circuit of the Rubik's cube: http://bruce.cubing.net/ham333/rubikhamiltonexplanation.html

Dimitri Leggas - 6 years, 8 months ago

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@Dimitri Leggas Bruce's work is impressive (I have worked with Bruce on other Rubik's Cube related mathematics), but not relevant to Muhtasim's comment. Rubik's Cube can be represented by a permutation group of finite order. From Lagrange's theorem, all elements (any sequence of face turns) starting from the identity (the solved cube) have an order (how many times the sequence is repeated before returning to the identity, or solved state) that must divide the order of the group. Since the group representing Rubik's Cube is finite, the order all its elements must therefore be finite. So, any sequence of moves applied to a solved cube will return to the solved state after a finite number of repetitions.

Joseph Miller - 6 years, 7 months ago

Can you explain what R U R' F mean?

Calvin Lin Staff - 6 years, 8 months ago

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@Calvin Lin It means rotate right face clockwise, up face clockwise, right face anticlockwise, front face clockwise

Agnishom Chattopadhyay - 6 years, 8 months ago

@Calvin Lin R- rotate the right face clockwise, U- rotate the top face clockwise, R'- rotate the right face anti-clockwise And F- rotate the front face clockwise

Ashwath Srikanthan - 6 years, 8 months ago

@Calvin Lin clockwise move right face R clockwise move Upper face U anticlock right R' clock front F

Rajat Maurya - 6 years, 8 months ago

@Calvin Lin Right up right inverse and up inverse

Shailesh Kumar - 6 years, 8 months ago

@Calvin Lin THESE R THE TYPES OF MOVE- R - MEANS TO MOVE RIGHT HAND SIDE OF CUBE VERTICALLY UPWARDS. U - MEANS TO MOVE THE UPPER SIDE OF CUBE TO THE LEFT SIDE. R' - MEANS TO MOVE RIGHT HAND SIDE OF CUBE VERTICALLY DOWNWARDS. F - MEANS TO MOVE THE FRONT SIDE OF THE CUBE TO THE RIGHT SIDE.

Harsh Shah - 6 years, 7 months ago

ok

Rostam Dana - 6 years, 8 months ago

These moves are trivial. Any algorithm operated repeatedly on a cube will result back in the Original configuration in finite repeatitions.

Agnishom Chattopadhyay - 6 years, 8 months ago

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I can agree

Raghu Raman Ravi - 6 years, 8 months ago

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It can be proven mathematically

Agnishom Chattopadhyay - 6 years, 8 months ago

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@Agnishom Chattopadhyay How?

Krishna Jha - 6 years, 8 months ago

The order of a sequence of moves is a matter of determining the effect on the sub-cubes as a permutation using disjoint cycle notation, then the order is the LCM of the cycle lengths. For RURFRUR'F the effect on the sub-cubes is a a 2-cycle on edge FR; a 5-cycle on edges UF, UL, UB, FL, and FD; and a 5-cycle on the 4 corners of the FF face (FUL, FUR, and FDL), and FDR. The LCM of 2, 5, and 5 is 10. Of note would be the maximal order which is 1260 of which DFDRU2DF'DR'U^2 is an example with shortest possible length in HTM (Half-Turn Metric, where turns of 90,180,90^\circ, 180^\circ, and 270270^\circ are considered a single move).

Joseph Miller - 6 years, 8 months ago

Those who know non commutative algebra can easily figure it out that each generator (RUR'F) forms a normal subgroup of order (here 10).
find n such that (RUR'F)^n=identity (means doing nothing on the cube) Eg: (RUR'F)^2=RUR'FRUR'F, among these some comnbinations can be replaced by other moves. Finally one can show (clever manipulations), (RUR'F)^10=Identity

Always Keep your total cube orientation in a fixed position during the moves. R- Right side face clockwise rotation U- upside face clockwise rotation R'- Right side face anti-clockwise rotation F-Front face clockwise rotation

rowthu vijayakrishna - 6 years, 8 months ago

There exist much more moves like this:

L'ULU do this 5 times

U'R 62 times

UL'U'L 6 times

RU'L'U 27 times

M'U 8 times

M'UM'U' 6 times

R2L2 12 times

and many more ........................................

Happy Cubing!!!!!!!

Kaustubh Bhargao - 6 years, 3 months ago

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R 4 times

math man - 6 years, 3 months ago

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Yes. That's the easiest "IDENTITY ALGORITHM "

Kaustubh Bhargao - 6 years, 2 months ago

R U' x63

math man - 6 years, 8 months ago

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Actually what are these 'R' 'U' 'F' ??

Kunal Gupta - 6 years, 8 months ago

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I too don't know.

Arindam Karmakar - 6 years, 8 months ago

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@Arindam Karmakar They are codes to tell you how to move the Rubik's cube. F is for Front. R: Right. L: Left. U: Under. F means turn the front side 90 degrees clockwise. F' means turn the front side 90 degrees anticlockwise.

C D - 6 years, 8 months ago

another move is F R U R'U'F'

Parth Lohomi - 6 years, 8 months ago

RU R'U'

Anmol Bhatia - 6 years, 8 months ago

Am I right in thinking that the number of moves given in any algorithm with as many moves as possible but repeated over a number of times, the number of times cannot be a prime number?

Victor Song - 6 years, 8 months ago

it's awesome !!

Tamanna Shwarno - 6 years, 8 months ago

what does RU R`F mean please???

Rostam Dana - 6 years, 8 months ago

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R means rotating the right face clockwise.. R' means to do the same in anticlock direction... U, F, D, B, L mean up, front, down, back, and lesft respectively...

Pankaj Joshi - 6 years, 8 months ago

cool. i liked it

Rostam Dana - 6 years, 8 months ago

Is there a way to predict how many times you have to do the move to get back to solve?

Josh Silverman Staff - 6 years, 8 months ago

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You have to program it. Look at this

Agnishom Chattopadhyay - 6 years, 8 months ago

You all can even try R' D' R D. I think it works with almost all of the algos. The number of times you have to do it may differ.

Ameya Salankar - 6 years, 8 months ago

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you could just take a cube and keep doing U R repeatedly and get the original configuration back.....but u need to have the patience as you have to do it quite many times..

Abhishek Bakshi - 6 years, 8 months ago

how to get fully solved cube?

aaron paul - 6 years, 8 months ago

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are you saying to solve the cube or about the above mentioned stuff

Abdur Rehman Zahid - 6 years, 8 months ago

VERRY VERRY EASY

Lester Nyroh Villanueva - 6 years, 8 months ago

@Rishabh Jain Try this, R'D'RD 6 times.. Same thing happens!

Pankaj Joshi - 6 years, 8 months ago

Do any random move repeatedly and it will get solved eventually not for this move only

Pranav Jain - 6 years, 8 months ago

I just did it and it does get solved

Abdur Rehman Zahid - 6 years, 8 months ago

not just only RUR'F , it works for almost all algorithms provided they are 4 moves

Murtuza Akhtari - 6 years, 8 months ago

Let me give you one more Take a solved rubiks cube and do the following 6 times FRUR'U'F'

ninad anklesaria - 6 years, 8 months ago

hey are u in fiitjee south delhi??? @Rishabh Jain

Kislay Raj - 6 years, 8 months ago

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no i am a commerce student from east delhi (totally opposite answer what you asked?)

Rishabh Jain - 6 years, 8 months ago

Doing the same move multiple times creates a subgroup of all moves, so by lagrange's theorem, the number of time you must repeat the move divides the number of possible combinations of the rubik's cube.

Taehyung Kim - 6 years, 8 months ago

normal position

Nagendra Giduturi - 6 years, 8 months ago

R= right side clock wise U= upper side clock wise R'=right side anti-clock wise F= front side clock wise

Mayur Desai - 6 years, 8 months ago

But i didn't get it !!!

sachin sharma - 6 years, 8 months ago

it remains same

Sameeranga Patwari - 6 years, 8 months ago

Can you explain what is RU R' F

Vaibhavi Warke - 6 years, 8 months ago

any particular move can do it not only this move :P

Ayush Maheshwari - 6 years, 8 months ago

Awesome

Morgan Holmstrom - 6 years, 7 months ago

6 repetitions and the cube will resolve itself.

well max - 6 years, 6 months ago

what does that mean

Coby Tran - 6 years, 6 months ago

Technically, this will happen no matter what sequence of moves one makes. It may take longer or shorter than 10 iterations, but because there are a finite number of positions for the cube, it has to eventually return to its original state.

Ron Glumpy - 6 years, 6 months ago

You could also repeat RUR'U' 6 times to achieve the same result.

Anirudh Swaminathan - 6 years, 5 months ago

What would be the biggest number of steps required to get a cube back in solved state for a 4-lettered algorithm...and what would be the algorithm.....i found that R'U is a big one

Abhishek Bakshi - 6 years, 2 months ago

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You will have to do it 62 times...

Kaustubh Bhargao - 6 years, 2 months ago

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I think 63 is the number.....RU has to be done 105..

Abhishek Bakshi - 6 years, 2 months ago

I found out that there are many such moves such as moving a solved cube 16 times with R U R' F B.

Harsh Shah - 6 years, 2 months ago

R x4 , R'x4 ,....

math man - 6 years, 8 months ago

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TEACH ME!!!!!!!!!!

Lester Nyroh Villanueva - 6 years, 8 months ago

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It is a bunch at internets

math man - 6 years, 3 months ago

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@Math Man Are you a speed cuber?

Which method do you use?

IF you use the CFOP method please tell me from where did you learn it?

I want to learn the same.Suggest me a better site for this.

Thank you :)

Kaustubh Bhargao - 6 years, 2 months ago

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@Kaustubh Bhargao i am a noob too solve a rubiks cube in 1min

math man - 6 years, 2 months ago

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@Math Man I am an intermediate one. I can solve a cube almost in 30 sec

Kaustubh Bhargao - 6 years, 2 months ago

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@Kaustubh Bhargao I do it in 40-50 seconds

Abhishek Bakshi - 6 years, 2 months ago

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@Abhishek Bakshi That's nice :) which method do you use?

Kaustubh Bhargao - 6 years, 2 months ago

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@Kaustubh Bhargao I use the common friedrich method, F2L, 2 look OLL and PLL, I don't remember PLL very well that's why it takes so much time..

Abhishek Bakshi - 6 years, 2 months ago

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@Abhishek Bakshi But i use the basic method. I want to learn Friedrich method. Please tell me from where did you learn it?

Kaustubh Bhargao - 6 years, 2 months ago

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@Kaustubh Bhargao I learnt it from youtube..

Abhishek Bakshi - 6 years, 2 months ago

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@Abhishek Bakshi OK. Thanks:)

Kaustubh Bhargao - 6 years, 2 months ago

@Abhishek Bakshi yes i tooo want to know which method do u use ?

Rishabh Jain - 6 years, 2 months ago
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