While the Rubik’s Cube is fascinating just as a toy, improving at it requires one to learn the process of ‘scrambling’. In this process, we follow along with moves generated by a computer program, in order to obtain a state of the cube that is fully randomly generated.
What Is Notation?
Notation refers to the combination of characters (such as alphabets) used to represent various turns on a puzzle, in the most intuitive way possible. So, it makes the process of scrambling uniform across the world, regardless of the cuber, software or cube being used.
Let us see what the basic idea behind notation is, first using the example of a 3×3 cube.
The Logic
Taking any cubic puzzle, there are six faces, giving rise to 6 independently maneuverable layers. So, considering these, we have the Right, Left, Up, Down, Front and Back layers on every cube. To represent these, we make use of the alphabets R, L, U, D, F and B, respectively.
In order to determine the direction in which to move these layers, we make use of suffixes, like an apostrophe (read as “prime”) or 2 (for double turns). So, for example, R’ refers to a 90 degree counterclockwise rotation of the right layer. B2 refers to a 180 degree rotation of the back layer. Some puzzles may have different scrambling techniques, such as the Clock, which has 9 dials and 2 faces, and involves a different notation (as will be discussed below).
The WCA Puzzles
For the 2×2 and 3×3 puzzles, the scrambling notation stays the same as discussed initially, with no changes/additions. For 4×4 and 5×5, there is the inclusion of moves with the suffix “w”, implying that they are wide layer turns, or turns of two layers at a time. For example, Rw’ means both right layers are turned together, counterclockwise by 90 degrees.
For 6×6 and 7×7, there is the inclusion of moves with a prefix “3”, in addition to the suffix “w”, which implies that you need to turn three layers at a time. For example, 3Lw2 means that all three of the left layers are turned together, by 180 degrees. For the Pyraminx, the moves represent turns of the corresponding side of the tetrahedral shape (4 axes), according to the corners. Also, lowercase letters correspond to only moving the corner-most tips. So, B implies finding the corner at the back, and moving that segment of the puzzle clockwise. Similarly, r’ implies moving the right corner tip counterclockwise.
For the Skewb, since we have FCN (as described above), the moves imply moving the corresponding layers of the puzzle about that corner. As with the pyraminx, even the skewb has 4 axes, so, for example, R would imply a clockwise turn of that entire face about the fixed red-green-white corner.
What does ‘FRU’ mean on the Rubik’s Cube?
‘FRU’ refers to a sequence of moves, say within an algorithm, that only involve moving the Front, Right and Upper faces throughout. These are often referred to as ‘gen’. So, if I have an algorithm with only R and U turns, it is considered a ‘2-gen’ algorithm (RU-gen). Hence, an algorithm with only F, R and U turns is a ‘3-gen’ algorithm (FRU-gen).
Conclusion
This article shows the various intricacies and notations involved in scrambling every puzzle, and over time, one can get comfortable with all of these and have a smooth scrambling experience. Initially, it may seem tough but you can take help of gancube robot which is intelligent Rubik cube solver shop now from official store, but with practice, it becomes second nature to us, and eventually we don’t even need to think about what we are doing as we scramble out of muscle memory!