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What is God's number in the slice turn metric?

TMOY

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Yeah, seems like it isn't known yet, but it's between 18 and 20.

I remember having read somewhere that we already know it is not 20, but I can't find where. Anyone can confirm ?

Anyway, since there are very few 20 HTM positions on the cube, checking them by brute force should be possible.
 

cuBerBruce

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Anyway, since there are very few 20 HTM positions on the cube, checking them by brute force should be possible.

The problem with this is we don't yet even know all of the 20 HTM positions. And just to be clear, the "very few" that we do know is over 1 million, and that's after reducing the number using symmetry/antisymmetry.
 

TMOY

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I said that it should be possible, not that it should be done right now. As soon as we reduce the number of potential 20 HTM positions to a reasonable number we can start using brute force on them to check their STM distance.

And when I say very few, it's relatively to the total number of positions of course. 1 million is manageable by any decent computer.
 
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guysensei1

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I said that it should be possible, not that it should be done right now. As soon as we reduce the number of potential 20 HTM positions to a reasonable number we can start using brute force on them to check their STM distance.

And when I say very few, it's relatively to the total number of positions of course. 1 million is manageable by any decent computer.

1 million optimal STM solutions? I think that may take quite a while.
 

TMOY

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I'm talking about the already known HTM-optimal positions. We only have to check that there exist shorter STM solutions for them, no need to find STM-optimal ones.
 

TMOY

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since all of these positions are possible with reguler moves (lets say instead of using M' using R2 L2) and gods number for that is 20 this should be 10 or less.

You obviously have no idea of what you're talking about, sorry. A STM solution does not use only slice moves.
(Actually the set of positions reachable with slice moves only is very small, only 768 positions IIRC.)
 

guysensei1

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superflip isnt possible using only slice moves...



ok lets do this once more.
all of the 3x3 positions can be made with wca recognized moves ( R,L,U,D,B and F), slice moves are basically two regular moves ( M2 being L2 R2).
since all scrambles that are scrambled with slice moves can be solved with regular moves in less then 20 moves using slice moves would be less than 10 moves.
that is cuz gods number is using only F,B,L,R,U and D moves and using 2 of those moves ( like i mentioned before M2 could be done by L2 R2) adn 20 : 2 = 10 so every cube scrambled with only slice moves used should be able to be solved with at most 10 slice moves.

You have no idea what STM actually is do you?

STM is like HTM, but with slice moves also counting as 1 move.
 
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