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The FMC thread

asacuber

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U2 F R2 U2 L2 B D2 L2
replace the F/B moves with wide moves (this brings the moves in the first half and the second half to the same axes):
U2 b U2 L2 D2 f D2 L2
replace the L2 moves with wide moves (this brings the moves in the first half and the second half to the same faces):
U2 b U2 r2 U2 b U2 r2 = (U2 b U2 r2)2

Essentially the same type of 3-cycle as (R2 U' R2 f2)2 and (R2 u' R2 f2)2.


Protip: Check your solution! Don't look at the cube when applying your solution; look only after you're done to check that your written solution really works.

Spending just a bit of time to check your solution drastically reduces DNF rates; it'd be kind of silly to spend an hour in an FMC attempt just to DNF it.
Thank you so much! I didn't even know the one marked in bold existed!
 

porkynator

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Lastly two questions: How many 8 move 2e2e are there and how often do you manage to find optimal domino finishes?
1. Good question! I am not sure. Right now I can think of:
a. (R2 F2 Rw2 U)*2
b. R2 F2 R2 U2 F2 R2 F2 U2
c. R2 F B U2 F' B' R2 F2 (same case as b.)
+ all shifts. There may be more.
EDIT: for example there is also M E2 M E2

2. No idea, but I think not that often. It seems fairly easy to get close to optimal though. I have only just started doing DR consistently and I have never checked for the optimal solution.

Good to see you back by the way!
 

irontwig

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1. Good question! I am not sure. Right now I can think of:
a. (R2 F2 Rw2 U)*2
b. R2 F2 R2 U2 F2 R2 F2 U2
c. R2 F B U2 F' B' R2 F2 (same case as b.)
+ all shifts. There may be more.
EDIT: for example there is also M E2 M E2

2. No idea, but I think not that often. It seems fairly easy to get close to optimal though. I have only just started doing DR consistently and I have never checked for the optimal solution.

Good to see you back by the way!
Cool, I'd expect there would be more, but many not. I like the holistic approach of DR; much like EO you try to massage the whole cube into a more pleasant state. However, as I'm not good at it yet (neither finding reductions or finishes), I kinda find it taking away time from other approaches.
 

guysensei1

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1. Good question! I am not sure. Right now I can think of:
a. (R2 F2 Rw2 U)*2
b. R2 F2 R2 U2 F2 R2 F2 U2
c. R2 F B U2 F' B' R2 F2 (same case as b.)
+ all shifts. There may be more.
EDIT: for example there is also M E2 M E2

2. No idea, but I think not that often. It seems fairly easy to get close to optimal though. I have only just started doing DR consistently and I have never checked for the optimal solution.

Good to see you back by the way!
[R2] (F2) R2 {U2} F2 [R2] (F2) {U2}

If you make a pair of moves in the same type of bracket wide, you get another alg for the same case

You can do this with more than one set of the bracketed moves too
 

trangium

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I got a 28 on the hardest scramble

Scramble: F U' F2 D' B U R' F' L D' R' U' L U B' D2 R' F U2 D2

B' U2 // pair
(U' F U2) // square
(L') // pair
(B' R) // 2x2x2

Now, go on normal, and notice that at the beginning, we can insert R, R', or R2 without disturbing the 2x2x2.
Inserting R' there sets up the yellow-blue edge, so a 2x2x3 can be made in just two more moves.

R' B' U2 // pair + inserted R'
(U' F U2) // square
(L') // pair
(B' R) // 2x2x2
F2 D // 2x2x3

Now, go on normal, and notice that at the beginning we can insert D, D', or D2 without disturbing the 2x2x3.
Of those options, inserting D' gave the best continuation.

D' R' B' U2 // pair + inserted R' and inserted D'
(U' F U2) // square
(L') // pair
(B' R) // 2x2x2
F2 D // 2x2x3
D F D2 L2 D // bad 6c in 16

Skeleton: D' R' B' U2 F2 D2 F D2 L2 D R' B L U2 F' U ^
^ [U' F U, B2] (8-5/19)

D' R' B' U2 F2 D2 F D2 L2 D * R' B L U' B2 U' F' U B2
* [D', L' U L] (8-3/24)

D' R' B' U2 F2 D2 F D2 L U' L D L' + U L R' B L U' B2 U' F' U B2
+ [R' D' R, U] (8-4/28)

Solution: D' R' B' U2 F2 D2 F D2 L U' L D L' R' D' R U R' D L B L U' B2 U' F' U B2 (28 HTM)

Edit: improved to 27

R' B' U2 // pair + inserted R'
(U' F U2) // square
(L') // pair
(^ B' R) // 2x2x2
F2 D // 2x2x3

Now, go on inverse, and notice that at the ^, we can insert D, D', or D2 without disturbing the 2x2x3.
Of those options, inserting D' gave the best continuation.

R' B' U2 // pair + inserted R'
(U' F U2) // square
(L') // pair
(D' B' R) // 2x2x2 + inserted D'
F2 D // 2x2x3
(F' U' F' U) // EO + preserve pair
(F' L2 F2) // 3c1t in 19

Skeleton: R' B' U2 F2 D F2 L2 F U' F U * F R' B D L U2 F' U
* [U' F' U, B'] (8-6/21)

R' B' U2 F2 @ D F2 L2 F B' U' F U F B R' B D L U2 F' U
@ [F2, L B L'] (8-2/27)

Final solution: R' B' U2 L B L' F2 L B' L' D F2 L2 F B' U' F U F B R' B D L U2 F' U (27 HTM)
 
Last edited:

WoowyBaby

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I got a 28 on the hardest scramble

Scramble: F U' F2 D' B U R' F' L D' R' U' L U B' D2 R' F U2 D2

B' U2 // pair
(U' F U2) // square
(L') // pair
(B' R) // 2x2x2

Now, go on normal, and notice that at the beginning, we can insert R, R', or R2 without disturbing the 2x2x2.
Inserting R' there sets up the yellow-blue edge, so a 2x2x3 can be made in just two more moves.

R' B' U2 // pair + inserted R'
(U' F U2) // square
(L') // pair
(B' R) // 2x2x2
F2 D // 2x2x3

Now, go on normal, and notice that at the beginning we can insert D, D', or D2 without disturbing the 2x2x3.
Of those options, inserting D' gave the best continuation.

D' R' B' U2 // pair + inserted R' and inserted D'
(U' F U2) // square
(L') // pair
(B' R) // 2x2x2
F2 D // 2x2x3
D F D2 L2 D // bad 6c in 16

Skeleton: D' R' B' U2 F2 D2 F D2 L2 D R' B L U2 F' U ^
^ [U' F U, B2] (8-5/19)

D' R' B' U2 F2 D2 F D2 L2 D * R' B L U' B2 U' F' U B2
* [D', L' U L] (8-3/24)

D' R' B' U2 F2 D2 F D2 L U' L D L' + U L R' B L U' B2 U' F' U B2
+ [R' D' R, U] (8-4/28)

Solution: D' R' B' U2 F2 D2 F D2 L U' L D L' R' D' R U R' D L B L U' B2 U' F' U B2 (28 HTM)

Edit: improved to 27

R' B' U2 // pair + inserted R'
(U' F U2) // square
(L') // pair
(^ B' R) // 2x2x2
F2 D // 2x2x3

Now, go on inverse, and notice that at the ^, we can insert D, D', or D2 without disturbing the 2x2x3.
Of those options, inserting D' gave the best continuation.

R' B' U2 // pair + inserted R'
(U' F U2) // square
(L') // pair
(D' B' R) // 2x2x2 + inserted D'
F2 D // 2x2x3
(F' U' F' U) // EO + preserve pair
(F' L2 F2) // 3c1t in 19

Skeleton: R' B' U2 F2 D F2 L2 F U' F U * F R' B D L U2 F' U
* [U' F' U, B'] (8-6/21)

R' B' U2 F2 @ D F2 L2 F B' U' F U F B R' B D L U2 F' U
@ [F2, L B L'] (8-2/27)

Final solution: R' B' U2 L B L' F2 L B' L' D F2 L2 F B' U' F U F B R' B D L U2 F' U (27 HTM)
WOW. I am impressed! You got 27 on the hardest scramble from cube20.org. I'm sure this must be the best anyone has gotten! My best is 30 which is nothing compared to this. You should be proud of yourself, good job!
 

WoowyBaby

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Hello Everyone! Today I have a number of fun little FMC related challenges!

1. Find the shortest solution you can: R' L2 F2 B2 F2 L' F2 R2 L2 B2 L R F' L F R' B' R F' L' F R' F2 R'
Optimal solution is extremely short! Can you find it?

2. Use slicey shenanigans to shorten this sequence!
D' F2 U2 D F2 U2 B2 D B2 D' L2 F2 D2

3. Find the shortest 3-corner skeleton possible!
U F2 U F2 R' F2 D R2 D R' L' U2 R2 B2 R' L' D2 F2 U2

4. Find a direct (no insertions) 8-move finish to this HTO state!
U D' L2 U' D R' L' D2 R U2 D2 R2 U2 D2 L' U2 D2

5. Orient all of the edges in just two moves!
D L2 B2 D R F2 R F' U2 B F' D' U2 R D U B' D2

Post your attempts / solutions here! I hope you have fun with these!
 
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Hello Everyone! Today I have a number of fun little FMC related challenges!

1. Find the shortest solution you can: R' L2 F2 B2 F2 L' F2 R2 L2 B2 L R F' L F R' B' R F' L' F R' F2 R'
Optimal solution is extremely short! Can you find it?

2. Use slicey shenanigans to shorten this sequence!
D' F2 U2 D F2 U2 B2 D B2 D' L2 F2 D2

3. Find the shortest 3-corner skeleton possible!
U F2 U F2 R' F2 D R2 D R' L' U2 R2 B2 R' L' D2 F2 U2

4. Find a direct (no insertions) 8-move finish to this HTO state!
U D' L2 U' D R' L' D2 R U2 D2 R2 U2 D2 L' U2 D2

5. Orient all of the edges in just two moves!
D L2 B2 D R F2 R F' U2 B F' D' U2 R D U B' D2

Post your attempts / solutions here! I hope you have fun with these!
1. R F L B L' F' R'
2. D' F2 U2 D * F2 U2 B2 D B2 D' L2 F2 D2 **
*=E2
**=E2

Shortened version: D' F2 D' B2 U2 F2 D F2 D' L2 B2 U2

3. F2 D R D' R2 D' L2 D
4. R2 U2 L2 F2 D2 L2 D2 L2
5. L (R)
 
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