• Welcome to the Speedsolving.com, home of the web's largest puzzle community!
    You are currently viewing our forum as a guest which gives you limited access to join discussions and access our other features.

    Registration is fast, simple and absolutely free so please, join our community of 40,000+ people from around the world today!

    If you are already a member, simply login to hide this message and begin participating in the community!

One-Answer 4x4 Question Thread

tano12345

Member
Joined
Jan 4, 2022
Messages
1
Location
Munich
20220104_172132.jpg20220104_172037.jpg
This is my cube. The sides that are not visible are solved properly (all white / all green).
Is it possible to solve it at all?
The cube got broken up accidentally and I'm unsure I assembled it correctly (its a long time ago).
I (believe I) can solve it via reduction and regular 3x3 algs. Is there a way to get the reduction wrong?
Thanks and please apologize if I violated some netiquette. First post here.
 

Christopher Mowla

Premium Member
Joined
Sep 17, 2009
Messages
1,109
Location
Earth
YouTube
Visit Channel
If you are going to include algorithm authors (which I support), you might as well go all the way and include date of discovery and links to original publications :)
I already did to the best of my ability.

Many, but not all, algorithms have this already. If they did not, they most likely came from a Cube Explorer search, for which it would be unknown who originally found it. Unless an algorithm, such as the 15 move single dedge flip by Frédérick Badie or Lucas Garron's lucasparity, was given specific credit for it, I did not credit anyone for it. I did not take credit for any of the algorithms I personally found in the <U2,D2,F2,B2,l,r> moveset with Cube Explorer (which are the majority of the unmarked algs) because of this.

In that link to the wiki, the algorithm with a [230] goes to the original source of the algorithm. And many of the special PLL cases are from yahoo groups, which was taken down a few years ago. But before they were, I backed up all such pages on to web.archive to preserve that history. (For example, an easy way to see these saved web-pages is to go see any of the links in the the PLL Parity algorithms sub-section of the External links sections.)

Also, I explained this in the second yellow block under this section in the Introduction.

EDIT:
It looks like [230] goes nowhere now, since Ben seem to recently delete (or move) his site. But the majority of the other links shouldn't be broken. (I know of one other one which is broken, as that went to another website other than speedsolving or twistypuzzles, but the majority of all links are to those two forums.)

That's debatable. (But if you want to debate, please use that thread, not this one. Thanks.)
 
Last edited:

cubingnobody

Member
Joined
Apr 8, 2022
Messages
5
Location
Tamil Nadu, India
So of course I know this is impossible but for some reason I've been trying to reduce my 4x4 to a 2x2. I've been trying since last night and now I'm on the last piece, the green-orange-yellow piece and the pieces are in a state where twisting the corner anticlockwise would be easier than moving and flipping the surrounding wing pieces. So in conclusion, I'm in need of an algorithm that twists a single corner and moves around only center pieces it touches and no other pieces (if it were okay to twist another corner I'd either use the beginner method technique or that algorithm with a lot of L and D moves). I hope something like this exists 🤞
 

xyzzy

Member
Joined
Dec 24, 2015
Messages
2,518
It's not possible to twist a single corner by itself. You really just have to move the three wing pieces around it instead.

(It's very much possible to do 4→2 reduction, just usually not recommended because it's much harder than the alternatives.)
 

cubingnobody

Member
Joined
Apr 8, 2022
Messages
5
Location
Tamil Nadu, India
It's not possible to twist a single corner by itself. You really just have to move the three wing pieces around it instead.

(It's very much possible to do 4→2 reduction, just usually not recommended because it's much harder than the alternatives.)
Thanks, but I'll just wait another day to see if anyone has an algorithm. The reason I think this may be possible is because I'm okay with a couple center pieces moving around.
 

xyzzy

Member
Joined
Dec 24, 2015
Messages
2,518
No, it's just impossible. Doesn't matter whether you allow moving centre pieces around or not.

(What would be possible is twisting a single corner, while also twisting a 2×2×2 corner block in the opposite direction. But the alg for doing this amounts to twisting two corners, then moving the edge pieces around one of them—which is basically what you wanted to avoid doing.)
 
Top