How do you calculate all the possible combinations on a Rubik's cube?

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Discussion Overview

The discussion revolves around calculating the total number of possible combinations of a Rubik's cube. Participants explore different approaches to understanding the permutations and constraints involved in the cube's mechanics, touching on both theoretical and practical aspects of the problem.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that the total combinations could be calculated by multiplying the number of faces by the nine cubes on each face, questioning their understanding of the problem.
  • Another participant points out that not all combinations are mechanically possible and suggests using programming to explore the permutations.
  • A participant with limited programming experience expresses uncertainty about how to approach the problem computationally.
  • One participant argues that counting permutations on a computer is infeasible due to the sheer size of the number, explaining that there are 8! permutations for corner cube locations and additional factors for orientations and edge cubes.
  • A later reply provides specific calculations for the number of combinations, presenting two different formulas that yield vastly different results, while noting that the larger number accounts for the different orbits of positions reachable through legal moves.

Areas of Agreement / Disagreement

Participants express differing views on how to approach the calculation of combinations, with some focusing on theoretical aspects and others on practical programming solutions. There is no consensus on a single method or understanding of the problem.

Contextual Notes

Participants highlight the complexity of the problem, including mechanical constraints and the limitations of computational methods for counting permutations. The discussion includes various assumptions about the nature of the cube's combinations and the feasibility of different approaches.

Nerdydude101
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I thought it would just be the number of faces multiplied by the nine cubes on each face? What am i doing wrong?
 
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Nerdydude101 said:
I thought it would just be the number of faces multiplied by the nine cubes on each face? What am i doing wrong?

Not all combinations are possible mechanically. I would probably try to solve this with a program. Are you comfortable writing a C program (or using some other programming language) to solve this?
 
I know very little programming, a tiny but if Python but that's about it
 
You're not going to be able to count the permutations on a computer. The number is too big.

If you consider the problem of the number of permutations that can be made by pulling a Rubik's cube apart piece by piece and then reassembling it, this is a huge number. There are eight corner cubes which can be placed. That means 8! permutations just based on corner cube location. Each corner cube can be placed in one of three orientations. That's a factor of 38 permutations on top of the 8! location permutations. The twelve corner cubes lead to two more factors, 12! and 212. Altogether, there are ##8! \, 3^8 \, 12! \, 2^{12}## permutations of the ripped apart and resembled cube. That is a *big* number.

Most of these permutations do not lead to the nice all colors on one face arrangement. There are constraints, but the final number is still huge.
 
See here
http://en.wikipedia.org/wiki/Rubik's_Cube
There are
$${8! \times 3^7 \times (12!/2) \times 2^{11}} = 43,252,003,274,489,856,000 \\

{8! \times 3^8 \times 12! \times 2^{12}} = 519,024,039,293,878,272,000. $$
combinations
the larger number is 12 times the smaller as there are 12 orbits
that is any position can reach 1/12 positions though legal moves separating possible moves into 12 orbits
 

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