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Random Cubing Discussion

mark49152

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mark49152
Additional information is always nice. What I dislike tho is that the profile's subsections are less compact compared to before.
Yeah I agree and I don't like that now only one event is visible at a time. It's irritating having to click the tabs especially when you also have to scroll left and right so much to see the content, on mobile.
 
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It is always important to have water nearby while deep in a cubing sesh. The other day I had to stop a sesh early because I realized I was insanely thirsty. Don't make my mistake.
 
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I recall having read that the pochmann style scrambling for megaminx cannot reach all megaminx positions, how is this proven?
You have (4^10)^7*2^7 different position in pochmann whixh is around 1.78e44 compared to around 20!*40!*3^20*2^20/2/3= 1.27e87 so dicounting symmetries for both is is fairly clear that pochmann would need quite a few more turns to even have the same number of possibilities (and would even then likely have many duplicate positions).

This is similar to how the lower bound of 18 was reached for 3x3.
 
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You have (4^10)^7*2^7 different position in pochmann whixh is around 1.78e44 compared to around 20!*40!*3^20*2^20/2/3= 1.27e87 so dicounting symmetries for both is is fairly clear that pochmann would need quite a few more turns to even have the same number of possibilities (and would even then likely have many duplicate positions).

This is similar to how the lower bound of 18 was reached for 3x3.
How did you get the number of positions for pochmann? I am confused
 
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How did you get the number of positions for pochmann? I am confused
It's just the number of turn sequences (and it turns out I got it slightly wrong but that actually reduces the number of positions) The correct calculation is (2^10)^7*2^7=2^77=1.51e23

2^10 because you have 10 R and D moves in each line (++ or -- each time) and when you do a U or U' you also have two choices (but 7 times so 2^7). The ^7 is because there are 7 lines
 
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2^10 because you have 10 R and D moves in each line (++ or -- each time) and when you do a U or U' you also have two choices (but 7 times so 2^7). The ^7 is because there are 7 lines
Wait, don't the standard scramble sequences always end with D++ U or D-- U' in each line? That would mean that there's no 2^7 contribution from the U and U' choice.
 
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Wait, don't the standard scramble sequences always end with D++ U or D-- U' in each line? That would mean that there's no 2^7 contribution from the U and U' choice.
They do but doesn't the U/U' affect the rotation so the R would affect different pieces depending on the combination of U and D moves wouldn't it?

In the same way that doing d U r2 is not the same as d U' R2 or d' U' R2
 
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They do but doesn't the U/U' affect the rotation so the R would affect different pieces depending on the combination of U and D moves wouldn't it?

In the same way that doing d U r2 is not the same as d U' R2 or d' U' R2
Yeah, but this ultimately doesn't affect the number of 70-move Pochmann-style scrambles, which is 2^70.
 
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