4x4x4 with only two alg's?

protocoldoug

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Hey guys, I'm learning the 4x4x4, and I'm not afraid to learn a few algs, but... To get started, the least number of algs would be helpful.

I'm seeing in a few places that solving the 4x4x4 is possible with a minimum of 2 algos?

...Namely the speedsolving wiki article on reduction ( http://www.speedsolving.com/wiki/index.php/Reduction_Method [in the info box it says 2 minimum]) and another recent post ( here )

But, I've been learning from speedcubing.com ( here ) and it seems that I'll need to learn 4 algs, 1 for edge step parity, 1 for OLL parity, and 2 for PLL parity.

Does anyone happen to have a link to a tutorial / vid / anything that describes how you can use just two algs?

I'd be super psyched up, thank you guys!
 
The intuitive portions doing the centers and aligning the edges -- I'm reallllly enjoying. It's a ton of fun. That part I've got down. But, I seem to be encountering more than 2 parity cases that require algos. So I'm referring to the algs that I've got on paper, however... I'm wondering: Maybe I'm doing a couple steps weird that are getting me there? Like, maybe there's a process I need to follow to get so there's only a couple cases.

Otherwise, maybe I'll just have to soldier up and learn all 4 (not a huge deal, but, thought someone might have a link on hand) that I've found.
 
You definitely don't need so many algorithms. All edges are intuitive, so no algorithms there. You'll need one for the dedge flip (OLL parity), and one for the PLL parity. The other PLL parity case can be transformed with a U Perm or other ways to get it into the same form.
 
@cyoubx: That's exactly what I was looking for :) Awesome man! Thank you, I'll start with those and experimenting on how to transform. Radness, I think I should be able to get these down relatively quickly (well, in a reasonable amount of time, these algs are hilariously long! :) ) Super fun, much appreciated.
 
@Kirjava, hahahaha. Yeah, it's takin' a long time solving it with only cube rotations XD

...But on the flip side, you're onto something along with cyoubx -- using only OLL and PLL parity, if I had the right cube rotation with the PLL parity I could solve the other cases I need to. However, my solutions are a little hacky now as I work out how to get the right permutations to get there (but I'm on the right track thanks to the help!!!) Thanks :)
 
you just learn one for the pll parity

dont forget the OLL parity

personally i use only two algs except the ones used on 3x3, its for the two different parities, but on 5x5 i only learned one more, and when a different parity shows up i use the same alg various times with some setup moves to fix the case, its slow, but im not focused on speed on 5x5 or higher :P
 
If you're referring to the parity algs, then just learn intuitive algorithms for each case (and yes there is one for each case). According to your count that would be 0 (zero) algs to solve the 4x4x4.
 
I dont think so TMOY. Because parities happen because you create a cycle of edges when doing reduction. However if you didnt do that and just use commutators for all the pieces then I dont think there would be parities. I might be wrong..

What most people call OLL parity is created (or not) by the scramble. Whether or not you create parity (or fix it) when reducing is independent of whether it was there from the start or not.

What most call PLL parity is created (or not) when pairing up edges.
 
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He means using commutators.

Ahhh ha! Interesting. Had to look it up TBH -- maybe a little beyond my current scope of just getting a 4x4x4 solve memorized. Buuut... None-the-less interesting. Thank you Kirjava, and also MaelSTRoM for pointing that out.

Link for the curious: http://www.speedsolving.com/wiki/index.php/Commutator

@Oljibe, cool, I was trying to set up some situations to see if I could fix the OLL parity with the PLL parity, but... no such luck. Thanks.

@cmhardw: Yeah, I guess by my count, I'm not counting the intuitive steps as algs. Learning the intuitive algs for the parity huh? Interesting! ...I am thinking about it :) Trying to get my head wrapped around it.

Rock on guys *thumbs up*
 
@cmhardw: Yeah, I guess by my count, I'm not counting the intuitive steps as algs. Learning the intuitive algs for the parity huh? Interesting! ...I am thinking about it :) Trying to get my head wrapped around it.

To be able to solve the different parity situations, you first need to understand them. First off, "parity error" is a terrible misnomer for what's really going on. Parity, in a mathematical sense, is usually used to refer to whether a set of things are in an even or odd permutation. Better stated we should not say that we have "OLL parity" but rather that the "wing edges have odd parity." Also, for the "PLL parity" it would be better to say that the "bandaged two piece wing edge groups parity does not match the corner parity."

Starting from there, you need to see how to fix each problem. To fix the wing edges having odd parity, you need to perform an odd permutation on them, changing their parity to even. The simplest odd permutation on wing edges is a single inner layer quarter turn. Now, this has some effects on the centers, but fixing them is the intuitive challenge :)

To get the bandaged two piece wing edge group parity to match the corner parity you can swap two bandaged edge groups. In order to do this you must realize that switching two groups like this is effectively performing double swaps on two pairs of wing edge pieces. Two double-swaps is an even permutation, so you can use commutators to do this.

I don't want to just tell you the algs, because then you'll view it as "algs" to learn. If you will have the patience to try these cases out, then come back to this thread with questions, then I guarantee that you will be able to solve the 4x4x4 completely intuitively. This will include the poorly named "parity errors".
 
@Oljibe, cool, I was trying to set up some situations to see if I could fix the OLL parity with the PLL parity, but... no such luck. Thanks.

well, that isnt possible what i know, I was just responding to the second post, saying he could do it with two algs, when it can acually be done with one, although its not speed optimal. also without thinking about it i managed to point that you can use the pll parity alg to set up an edge cycle, or use an edge cycle to set up the pll parity,

and dude, im rocking on already! *thumbs up back*
 
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