# How do you solve this commutator optimally?



## Repsela (Jul 9, 2014)

Hi Considering this comm: FD (buffer) RB DR what is the optimal and fastest way to solve it?


----------



## yoinneroid (Jul 9, 2014)

Repsela said:


> Hi Considering this comm: FD (buffer) RB DR what is the optimal and fastest way to solve it?



What I do: x y' R' U M2 U' R U M2 U' y x'
What I wish I would do: B M2 U R2 U' M2 U R2 U' B'
What is probably faster: Uw R U' M2 U R U' M2 U R2 Uw'


----------



## Tao Yu (Jul 9, 2014)

yoinneroid said:


> What I do: x y' R' U M2 U' R U M2 U' y x'
> What I wish I would do: B M2 U R2 U' M2 U R2 U' B'
> What is probably faster: Uw R U' M2 U R U' M2 U R2 Uw'


You're using the buffer DF instead of FD...

I would use x y F' R U M' U2 M U R' F y' x' (this is a setup to a 4 move comm)


----------



## Ollie (Jul 9, 2014)

yoinneroid said:


> What I do: x y' R' U M2 U' R U M2 U' y x'
> What I wish I would do: B M2 U R2 U' M2 U R2 U' B'
> What is probably faster: Uw R U' M2 U R U' M2 U R2 Uw'



*FD* buffer

Optimal is 10 HTM, but the speed-optimal alg is much better and it's only one move extra.

Uw R U M' U' R U M U' R2 Uw'

edit: ninja'd. And also, in future this should go in the One Answer BLD Question Thread


----------



## Nicck (Jul 9, 2014)

here are some that are optimaler - 9 STM - but not center-safe:

[ R' U F' ; F2 E' F2 E ] = R' U F E' F2 E F U' R
[ R' B' D' ; D2 S D2 S' ] = R' B' D S D2 S' D B R
...
...

conjugated 4-movers, each with an A9 and B9 version (invert last setup turn and 4-mover of A9 version to get B9 version)

EDIT: yup. ouch.


----------



## Parham Saeednia (Jul 9, 2014)

What i do is :
z' x' D' M' U' R U M U' R' U D x z 
10 move


----------



## Stefan (Jul 9, 2014)

Repsela said:


> Considering this comm: FD (buffer) RB DR



That's not a commutator. That's a case.

Commutators are move sequences of a certain type (ABA'B') and they can be used to solve cases.


----------



## Repsela (Jul 9, 2014)

Ollie said:


> *FD* buffer
> 
> Optimal is 10 HTM, but the speed-optimal alg is much better and it's only one move extra.
> 
> ...



Ok thank you


----------



## A Leman (Jul 9, 2014)

FD is not my buffer and I don't rotate too often with UF, but this may be worth a try.
z'U'rUMU2M'Ur'Uz


----------

