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When solving a 4x4 cube you have specific notation to inner and outer lines, like R = Clockwise outer right and r = Clockwise inner right. If you want to turn both, the two letter must be combined like Rr, (Rr)' or (Rr)2. To solve OLL parity I could use the following algorithm:

enter image description here

Image linked from speedcubing.com

r2 B2 U2 l U2 r' U2 r U2 F2 r F2 l' B2 r2

If r2 means "turn inner right 2 times clockwise", why some sites uses r as Rr?

Example:

  1. Open Alg Cubing
  2. Select 4x4 cube
  3. Inside the Moves field, type r
  4. Play. It will turn both right columns.

Related Stuff:

  • This site uses the notation r to define "both layers(outer and inner)".
  • However, this site uses the notation Rrto define "both layers"

My question: What is the official notation to 4x4 movements(if any exists)?

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  • $\begingroup$ The "another example" site that you linked refers to the inner-right slice as r and the outer-right slice as R. This appears to be consistent with the other two sites. $\endgroup$ Apr 14, 2015 at 18:59
  • $\begingroup$ Take a look at the Notations section of that site: "1. Lower-case letters mean turning 2 layers of the corresponding face. 2" before the face letter (e.g. 2R) means moving only the internal layer of the corresponding face. ". To this site r means both layers and 2R means inner layer $\endgroup$
    – user11399
    Apr 14, 2015 at 19:01
  • $\begingroup$ I see. That seems really wrong and misleading. $\endgroup$ Apr 14, 2015 at 19:11

3 Answers 3

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There is an official scramble notation for WCA competitions (which has continued to change over the years), which uses Rw as (Rr), 3Rw as (l' r R), and so forth.

You will notice on that page that they do not have symbols designated for inner slice turns only because the WCA scrambles cubes using outer block turns only to follow the outer block turn metric (OBTM). However, SiGN notation, as you have seen on alg.cubing.net, is used more often now than previously.

Clearly a move such as Rw = (Rr) which is used for WCA scrambles is never mistaken for an inner slice turn, for example; and thus a good rule of thumb for the casual cuber who wishes to communicate his algorithms to others is to have the courtesy to label the notation next to the alg if the algorithm does not use "Rw" moves (clearly Old WCA) 2R2 moves (clearly SiGN).

Taking the edge flip alg you posted, for example:

r2 B2 U2 l U2 r' U2 r U2 F2 r F2 l' B2 r2 (Old WCA notation).

Lastly, it's even better to link your algorithms to a site like alg.cubing.net (for SiGN notation) or alg.garron.us (for old WCA notation), so that those who do not know of a notation at all can still see the algorithm with a click of a play button.

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  • $\begingroup$ Good answer sir. That is the one i was expecting :) . It is just a matter of those sites to make it visible what notation they are using. And i also agree that SiGN notation is better on cubes with more than 4 lines/rows, due to the first positional number. $\endgroup$
    – user11399
    Apr 15, 2015 at 3:12
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Notation is just a way of expressing sequences of moves. The notation used can change depending on who's doing the notating, and this is true of all higher-dimensional puzzles. There's not really a standard way to notate, any more than the symbols we use for physics are standard. It'd be inconvenient to switch, but we certainly could.

As an example, the Trignis has very different notation depending on the method the solver used to solve the puzzle.

Consequently, there is no standard notation per se for higher-dimensional twisty puzzles. I more often see R for the rightmost, r for inner right, l for inner left, and L for far left; however, this is by no means necessarily universal. I've also seen eL/eR on the 4x4 and 5x5 for "edge-wing left" and "edge-wing right" - it just depends on convenience.

Be sure you check with the guide you're following to see what their notation is for cube movements.

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I've found this, which explains the notation of 4x4 cube.

http://www.speedcubing.com/chris/4-presolution.html

Basically, you have the same letters of the 3x3 (U R F B L D), upper-case if referring to external layers, lower-case if referring to internal layers.
This kind of notation is commonly used in many websites and guides.
You ask: "Is this official?"
The answer is no! As far as I know, nobody (except Erno Rubik) can say "this is official, this isn't official". In fact, there's no need to establish an official notation for the Rubik's cube.
This doesn't exclude the existence of (useful) conventions, though unofficial!
Currently, the preferred notation is the one described above, with capitals and lower-case letters.

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  • $\begingroup$ Being the creator of something does not mean that only this pearson(creator) has the rights to compile standards for its creation. There is World Cube Association, that is doing the job to create a more complete standard to cube notations. The matter here, after reading the accepted answer is just that sites does not want to follow those best practices... $\endgroup$
    – user11399
    Apr 16, 2018 at 16:35