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What are 2-gen algorithms?

rubiknewbie

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I heard people talk about this. Is it algorithms that only deal with 2 faces? Got some examples?
 

AvGalen

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2 Gen means "consisting of 2 generators". Those 2 generators could be something as basic as [R] or something really complicated.
So any algorithm that consists of only R R2 R' U U2 U' is considered 2 gen.
So are algorithms that consists of only M M2 M' U U2 U' (slice-algs).
And so are algorithms that consist of only L L2 L' U U2 U' (mirrored or lefthanded algs)

BUT because the generators could be chosen as
f and b (double layers) that means that fbfbffb is 2 gen as well

And technically you could argue that (U L' F r') (B d') (U L' F r') (B d') is 2 gen as well, but nobody really means that when they say 2-gen

(if you choose the two generators as [ULFRBD] and [ulfrbdxyzMES] basically everything becomes 2 gen but again that is not what people mean when the say 2-gen)
 

Akuma

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"2 gen" algorithm is an algorithm consisting of only 2 kinds of moves in a repeated patterns. Usually R and U movements.

The reason why attention are given to these is because R and U algorithms can be preformed very fast and very fluid thus these algorithms are usually desired amongst speedcubers. A lot of algorithms can be re-designed to only be using R and U moves but the drawback is that the algorithm sometimes becomes longer or harder to remember due to the monotony of the algorithm.
 

cincyaviation

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What method uses a lot of R U 2-gen?

such an un-needed bump, there is the 1AQT for a reason, but to answer your question, roux and petrus both build blocks and then orient edges, enabling the rest of the cube (only the rest of F2L for petrus i think) to be solved in 2 gen (M,U for roux and R,U for petrus) and ZZ orients all edges to begin with, so that the whole F2L can be done in 3 gen with no cube rotations
 

Edward

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What method uses a lot of R U 2-gen?

such an un-needed bump, there is the 1AQT for a reason, but to answer your question, roux and petrus both build blocks and then orient edges, enabling the rest of the cube (only the rest of F2L for petrus i think) to be solved in 2 gen (M,U for roux and R,U for petrus) and ZZ orients all edges to begin with, so that the whole F2L can be done in 3 gen with no cube rotations

It was a perfectly relevant bump, and you have been ninja'd.
 

cincyaviation

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What method uses a lot of R U 2-gen?

such an un-needed bump, there is the 1AQT for a reason, but to answer your question, roux and petrus both build blocks and then orient edges, enabling the rest of the cube (only the rest of F2L for petrus i think) to be solved in 2 gen (M,U for roux and R,U for petrus) and ZZ orients all edges to begin with, so that the whole F2L can be done in 3 gen with no cube rotations

It was a perfectly relevant bump, and you have been ninja'd.
i didn't think it was that relevant, and i saw your post before i made mine >_>
Whats that smiley even mean BTW? :p
 

miniGOINGS

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such an un-needed bump, there is the 1AQT for a reason, but to answer your question, roux and petrus both build blocks and then orient edges, enabling the rest of the cube (only the rest of F2L for petrus i think) to be solved in 2 gen (M,U for roux and R,U for petrus) and ZZ orients all edges to begin with, so that the whole F2L can be done in 3 gen with no cube rotations

Kind of...

Petrus usually goes ...EO --> <R, U> --> LL
Whereas Roux usually goes ...CMLL --> <M, U>

Roux EO is part of the <M, U> phase.
 

Sharkretriver

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What method uses a lot of R U 2-gen?

such an un-needed bump, there is the 1AQT for a reason, but to answer your question, roux and petrus both build blocks and then orient edges, enabling the rest of the cube (only the rest of F2L for petrus i think) to be solved in 2 gen (M,U for roux and R,U for petrus) and ZZ orients all edges to begin with, so that the whole F2L can be done in 3 gen with no cube rotations
wtf is the 1AQT just wondering.
 

riffz

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What method uses a lot of R U 2-gen?

such an un-needed bump, there is the 1AQT for a reason, but to answer your question, roux and petrus both build blocks and then orient edges, enabling the rest of the cube (only the rest of F2L for petrus i think) to be solved in 2 gen (M,U for roux and R,U for petrus) and ZZ orients all edges to begin with, so that the whole F2L can be done in 3 gen with no cube rotations
wtf is the 1AQT just wondering.

The "One Answer Question Thread" that is stickied at the top of this forum section. :)
 
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