[HN Gopher] 34x34x34 Rubik's Cube
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       34x34x34 Rubik's Cube
        
       Author : Brajeshwar
       Score  : 182 points
       Date   : 2024-10-27 15:06 UTC (5 days ago)
        
 (HTM) web link (ruwix.com)
 (TXT) w3m dump (ruwix.com)
        
       | russellbeattie wrote:
       | Pfffft. Old news. How about a 49x49x49 cube instead?
       | 
       | https://m.youtube.com/watch?v=4ZeylpCG3IE
        
         | PaulRobinson wrote:
         | From the original article on the 34x34x34 "record":
         | 
         | > It took about 1 year, and 1000 work hours to make the cube.
         | 
         | Imagine doing all that work, all the planning, designing,
         | printing, assembly, and feeling the title will be yours soon,
         | knowing the record has stood unbroken for 7 years, confident
         | you're the only person even trying...
         | 
         | ... And then 4 weeks before you finish a guy appears on YouTube
         | with his 49x49x49...
         | 
         | Ooof.
        
           | falcor84 wrote:
           | Nah, TFA was published on May 10, 2024, so he did hold the
           | record for almost half a year.
        
             | mega_dean wrote:
             | In the 49x49x49 video, he goes over previous world records
             | of "Highest Order nxnxn Twisty Puzzle", and I thought it
             | was weird he didn't mention the 34x34x34. But in the
             | youtube description, he links to this forum post where he
             | announces it on August 10 (a few weeks before the video,
             | but still well after May 10):
             | https://www.twistypuzzles.com/forum/viewtopic.php?t=39559
             | There is a comment from the creator of the 34x34x34:
             | 
             | > Ah there's so much I want to say, where to begin? Well,
             | soon after finishing the 34x34, I notified Greg, who
             | immediately notified me about the 49x49. At that point,
             | Preston had already checkered the 49x49, so I did not
             | consider the 34x34 a world record. It seems nobody noticed
             | this, but nowhere in any of my videos did I claim the 34x34
             | was a world record :lol: But still, everyone just assumed
             | it was :lol:
        
               | Aardwolf wrote:
               | Apparently an even-sized cube is harder to make though so
               | it should count as the record for even-sized cube
        
           | Vampiero wrote:
           | The previous record was 33x33x33. Imagine going through all
           | that just to beat it by one unit while using the same design,
           | that's so cheap.
           | 
           | I'm so glad he was beaten by the 49x49x49.
        
           | Brajeshwar wrote:
           | I don't think the 49 guy was even attempting in a hurry. It
           | took him 4+ years, right.
        
           | queuebert wrote:
           | FYI this is exactly what being a research scientist feels
           | like.
        
         | Brajeshwar wrote:
         | I'm sorry I was not good with my search. I actually found a
         | 33x33x33, and then the next highest that popped up was this
         | 34x34x34. Next time, I will see if I should spend more time
         | searching for higher records in any record-breaking event.
        
       | tetris11 wrote:
       | After the 22x22x22, the how seems to no longer be an issue and
       | it's more about scaling the cube to the minimum density of the
       | printer.
       | 
       | That, and clearly money.
        
       | qwertox wrote:
       | The video at the bottom of the page is a work of art.
       | 
       | Now someone should build a robot to actually work that thing.
       | 
       | https://www.youtube.com/watch?v=ocy09pzME4E
        
         | Modified3019 wrote:
         | Wow no kidding, I actually watched the whole thing.
         | 
         | The stop motion of the build was very satisfying. It's also
         | amazing how smoothly it moves, even being as heavy as it is.
        
         | Brajeshwar wrote:
         | A few days ago, my younger daughter was trying to have fun and
         | suggested that we watch an important video about solving a
         | 1x1x1 Rubik's Cube. I went along, and we spent some time moving
         | up the numbers; that's when we needed to search for the largest
         | number of NxNxN possible, and we landed on this video and the
         | article.
        
           | nick__m wrote:
           | Isn't a 1x1x1 rubik's cube a dice ? Or i am missing something
           | about the size notation ?
        
             | Brajeshwar wrote:
             | My daughter was making fun of me!
        
             | tetris11 wrote:
             | You still have to solve the minimum number of rotations to
             | get the "1" at the top and the "3" in front
        
               | jandrese wrote:
               | Isn't the minimum number of rotations always 0? IE you
               | start with an already solved cube?
               | 
               | Maximum number of rotations is more interesting, although
               | in the 1 cube that is just 2.
        
               | tromp wrote:
               | The minimum is not over all starting configurations, but
               | over all move sequences for a fixed starting
               | configuration.
        
       | Oreb wrote:
       | From a puzzle-solving point of view, these very large cubes
       | aren't that interesting. When you increase the cube size, there
       | are new things to figure out, but only up to a certain point.
       | Figuring out how to solve a 4x4x4 when you know how to solve a
       | 3x3x3 takes some significant work. I think I spent a whole
       | weekend to successfully solve a 4x4x4 the first time I got one,
       | despite being reasonably good at solving the 3x3x3. Solving a
       | 5x5x5 for the first time took just a couple of hours, there
       | wasn't much new to learn. The 6x6x6 was easier still. When I got
       | to the 7x7x7, there wasn't really anything new at all. I could
       | solve it immediately, it just took more time.
       | 
       | Anything beyond 7x7x7 is pretty much the same. It's just more
       | annoying, because the puzzle gets physically harder to handle,
       | and because you have to do the tedious work of counting how many
       | layers away from the centre a piece is. The 7x7x7 is the biggest
       | cube used in official competitions, for a good reason.
       | 
       | The motivation for making enormous cubes like the 34x34x34 is
       | just the engineering challenge, and breaking records. Nobody is
       | going to want to solve such a thing, at least not more than once.
        
         | matsemann wrote:
         | Just to elaborate: Solving a 5x5x5 or a 7x7x7 is basically just
         | turning the cube into a 3x3x3 by lining up the edges and fill
         | in the centers. Which is a new thing, but quite easy to figure
         | out. And then solve it as if it was a 3x3x3.
        
           | Oreb wrote:
           | That's not the only way to solve big cubes, but it's indeed
           | the most common way (known as "reduction"), and what most
           | people naturally come up with if they try to solve 4x4x4 or
           | bigger on their own. In addition to what you said, there is
           | also the issue of parity (basically, when you reduce a 4x4x4
           | to a 3x3x3 by solving centers and edges first, you will often
           | end up with a 3x3x3 cube in an unsolvable state, and you need
           | to figure out some tricks to convert it to a solvable state),
           | but if you know how to solve parity problems on a 4x4x4, you
           | can do it for a cube of any size.
        
             | golf_mike wrote:
             | Just out of curiosity (no rubiks cube affinity at all), but
             | how can there be an unsolvable state when there are
             | 'tricks' get in a solvable state? Does that not imply that
             | there are no unsolvable states at all? Or is that maybe
             | related to a certain method of solving?
        
               | glomph wrote:
               | They mean that the outer 3x3 is unsolvable taken in
               | isolaton. The tricks will involve unsolving the middle
               | faces and solving them again.
        
               | golf_mike wrote:
               | thanks!
        
               | Oreb wrote:
               | The reduction method means reducing a big cube (NxNxN for
               | N>3) to a 3x3x3 cube by first solving the centers (the
               | central (N-2)x(N-2)x(N-2) square on each face) and the
               | edges (the inner N-2 pieces along each edge of the cube).
               | You are then essentially left with a 3x3x3 cube that you
               | can try to solve by only turning the outer layers (which
               | won't break the centers and edges you solved in the first
               | stage).
               | 
               | The problem with this is that you may end up with a 3x3x3
               | cube that is not solvable. For instance, you can get a
               | state where the entire cube is solved, except for two
               | edges that need to swap locations. This isn't possible.
               | In group theoretical language, only even permutations are
               | possible. You can swap two _pairs_ of edges, but not just
               | two edges.
               | 
               | When you end up in such an unsolvable 3x3x3 cube, you
               | have to temporarily turn the inner layers of the cube and
               | break apart the centers and edges you built in the first
               | step, and then reassemble them again to a solvable 3x3x3
               | cube.
        
               | golf_mike wrote:
               | thanks!
        
             | hinkley wrote:
             | The moves to fix parity made the 4x4x4 less fun for me. The
             | recommended solution is long.
             | 
             | The hollow 3 has a similar problem. Because you can't see
             | the central piece there's a way to rotate the core and a
             | couple of edge pieces so they look like they violate
             | parity.
        
         | psychoslave wrote:
         | Interesting, make me wonder what are the well known algorithms
         | to solve them and how they compare in term of complexity.
        
         | JKCalhoun wrote:
         | That all sounds like fun but I'm still working through solving
         | a 64-disc Tower of Hanoi puzzle right now and won't be able to
         | get to another puzzle for a bit.
        
           | anonu wrote:
           | Lol, minimum moves needed 2^64-1
        
           | jerf wrote:
           | I'm still waiting for my Moment of Glory when a puzzle room
           | or something has a Hanoi tower and I can slam out the
           | solution as quickly as I can move the pieces, thus justifying
           | all my formal Computer Science education once and for all.
           | 
           | (There is a very easy-to-remember algorithm that can be
           | trivially executed by humans given here in a Mathologer
           | video, with a time-code link to jump straight to it:
           | https://youtu.be/MbonokcLbNo?si=ey8bv4T9KbDxgB7N&t=650 )
        
         | sebzim4500 wrote:
         | It is my understanding that a 5x5x5 is actually more similar to
         | a 3x3x3 than a 4x4x4 is.
        
           | Oreb wrote:
           | Sort of. The 3x3x3 and 5x5x5 both have fixed, immovable
           | centers. Red is always opposite orange, blue is always
           | opposite green, and yellow is always opposite white. The
           | 4x4x4 doesn't have fixed centers. When you build the central
           | 2x2 squares on each side (the first step of the reduction
           | method), you have to be careful to have the colors arranged
           | in the correct locations relative to each other. In a certain
           | sense, this is trivial, but it forces you to remember exactly
           | where all colors are on a solved cube in order to solve a
           | 4x4x4 (or other even sized cubes). Odd sized cubes don't have
           | this problem.
           | 
           | Another annoying thing about 4x4x4 compared to 5x5x5 is that
           | you have two possible types of parity issues on the 4x4x4. On
           | the 5x5x5, only one of these can occur.
           | 
           | Nevertheless, if you know how to solve a 3x3x3 and no bigger
           | cube, a 4x4x4 is certainly the easiest next step.
        
             | JonChesterfield wrote:
             | Remember where the colours are when solved is overstating
             | it a bit, you can look at the corners for the answer.
             | Otherwise yep.
        
         | woodrowbarlow wrote:
         | i was clicking around on the site and found an interesting
         | article about other attempts to make cubes more challenging --
         | 
         | https://ruwix.com/twisty-puzzles/bandaged-cube-puzzles/
         | 
         | in particular, "bandaged cubes" in which certain faces have
         | fused blocks to limit your available moves, and "constrained
         | cubes" in which certain faces can only rotate in one direction,
         | and only by a certain amount.
        
           | GuB-42 wrote:
           | One of the hardest Rubik's cube I have seen is a regular
           | 3x3x3, but with stickers that change color depending on the
           | angle you look at them from.
        
             | seabass-labrax wrote:
             | I'd like to try that! Do you remember what it was called?
        
               | GuB-42 wrote:
               | There is the "Rubik's Impossible"
               | 
               | https://www.rubiks.com/products/rubiks-impossible
               | 
               | Sticker sets are also available, like this one
               | 
               | https://oliverstickers.com/two-face-3x3x3.html
        
             | brianleb wrote:
             | I'm not a cuber or a puzzle guy or a math guy, but I am
             | curious: how do you know when it's solved? Or is this a
             | 'whoosh' moment and I'm missing the obvious?
        
         | jquery wrote:
         | The engineering challenge of making such a 34^3 cube is way
         | higher than that of solving. It's incredible impressive what
         | dedication is capable of.
        
       | user2342 wrote:
       | Are there recommendable sources on how to learn solving/the
       | concepts of a classic cube?
        
         | QuadmasterXLII wrote:
         | are you looking for a classic cube specific source, or
         | techniques that will solve much slower but generalize to other
         | shapes of permutation puzzle?
        
           | user2342 wrote:
           | Rather for the classic 3x3x3 cube. I played with it in the
           | 80ies, but never understood the concepts behind it.
        
         | bembo wrote:
         | The website this post is on is a wiki that explains how to
         | solve a lot of different puzzles like the rubix cube.
        
           | user2342 wrote:
           | Thanks. Looks promising!
        
           | Hackbraten wrote:
           | I'm having a really hard time to understand even the
           | "beginner's method" on that wiki.
           | 
           | For example, it entirely glosses over how to solve the
           | ,,first two layers" (F2L) on the left and back faces. It only
           | ever explains F2L for the front and right faces. However, I
           | can't possibly achieve a ,,yellow cross" that way. I wonder
           | why I can't seem to find any source that actually explains
           | it.
        
             | Oreb wrote:
             | I generally prefer written tutorials over video tutorials,
             | but cubing related stuff is an exception. Videos are easier
             | to digest.
             | 
             | Here's a good beginner tutorial:
             | 
             | https://www.youtube.com/playlist?list=PLBHocHmPzgIjnAbNLHDy
             | c...
        
         | Oreb wrote:
         | There are a lot of methods, optimized for different purposes.
         | Some are easy to learn, but take a very large number of moves
         | to solve the cube. Some are exactly the opposite: Difficult to
         | learn, but enables you to solve the cube in just a few seconds.
         | Others are optimized for solving the cube in the fewest
         | possible number of moves, but requires so much thinking that
         | they are not suitable for fast solutions. Others again are
         | optimized for blindfolded solving.
         | 
         | My two favorite methods are Roux and 3-style.
         | 
         | Roux is the second most common method for speedsolving.
         | Compared to the more popular CFOP method, Roux is more
         | intuitive (in the sense that you mostly solve by thinking
         | rather than by executing memorized algorithms), and requires
         | fewer moves. Roux is much more fun than CFOP, if you ask me,
         | and for adults and/or people who are attracted to the puzzle-
         | solving nature of the cube rather than in learning algorithms
         | and finger-tricks, I think it's easier to learn. Kian Mansour's
         | tutorials on YouTube is a good place to start learning it.
         | 
         | 3-style is a method designed for blindfolded solving, but it's
         | a fun way to solve the cube even in sighted solves. It's a very
         | elegant way to solve the cube, based on the concept of
         | commutators. It takes a lot of moves compared to Roux, but the
         | fun thing is that it can be done 100% intuitively, without any
         | memorized algorithms (Roux requires a few, though not nearly as
         | many as CFOP). It's satisfactory to be able to solve the cube
         | in a way where you understand and can explain every single step
         | of your solution. As an added bonus, if you know 3-style, you
         | can easily learn blindfolded solving, which is tremendously
         | fun, and not nearly as difficult as it sounds.
         | 
         | Edit: If you do decide you want to learn, make sure you get a
         | good modern cube. The hardware has advanced enormously since
         | the 1980s, modern cubes are so much easier and more fun to use.
         | There are plenty of good choices. Stay away from original
         | Rubik's cubes, get a recent cube from a brand like Moyu, X-man
         | or Gan.
        
           | z5h wrote:
           | I'll add my vote for Roux in terms of pure fun. And there is
           | more freedom to play between fastest solves and fewer moves
           | with more planning.
        
           | chrisshroba wrote:
           | I used to be able to solve the 3x3 in high school using
           | memorized algorithms and then I lost interest since there was
           | no reasoning involved. Your comment makes me want to pick it
           | back up and learn 3-style, so thank you for the clear
           | explanation!
        
             | vikingerik wrote:
             | If what's fun is the reasoning, then the thing to do is
             | other shapes and styles of puzzles besides the cube.
             | 
             | This is my collection: https://imgur.com/v9OuYNw
             | 
             | Like you, I learned the 3x3x3 in high school via memorized
             | algorithms, and that was only so interesting. Years later
             | my brother got me a Megaminx (the dodecahedron equivalent
             | to the 3x3x3 cube, third one in the top row there) and I
             | was absolutely fascinated by learning to solve that by
             | porting what I knew from the cube. From there I got all
             | those other shapes as well. The most interesting ones to
             | search by name: Dayan Gem 3 (the one that looks like the
             | Star of David), Face-Turning Octahedron (last one in the
             | second row), Helicopter Cube (to the right of the 3x3x4),
             | Rex Cube (right from the Helicopter Cube).
        
             | billmcneale wrote:
             | Even with CFOP, there is a large amount of intuition needed
             | in order to break below the 25 second limit, mostly because
             | of lookahead. During that phase, you need to train your
             | fingers to do moves while your brain anticipates the next
             | moves. There are no real formulas involved, it's really
             | about intuition, pure skill, and multitasking.
             | 
             | I have hit a wall there personally.
        
           | spencerchubb wrote:
           | I love the Roux method! I just went to a competition this
           | weekend and got my personal record of 9.39 second average
           | with Roux.
           | 
           | The unfortunate part is that beginner tutorials for Roux kind
           | of suck.
        
             | Oreb wrote:
             | Congrats, that's an awesome average! I wish I was that
             | fast. I don't time myself often, but when I do, I usually
             | end up somewhere around 15 seconds. My efficiency is not
             | bad, but my hands are just too slow.
             | 
             | I agree about beginner tutorials. There are some decent
             | Roux tutorials, but they are mostly not targeting complete
             | beginners. I believe it should be possible to make a Roux-
             | based beginner method that is even simpler than the popular
             | layer-by-layer beginner methods most new cubers learn. If
             | you think about it, it seems almost obvious. If efficiency
             | is not a concern, the first two blocks of Roux have to be
             | simpler than the first two layers of a layer-by-layer
             | approach, since you are solving a subset of the first two
             | layers. CMLL is also obviously simpler than the CFOP last
             | layer. The only thing that remains is the last six edges,
             | and that's simple enough that I think beginners could
             | figure out by trial and error. With the right
             | simplifications (at the expense of efficiency) and good
             | pedagogy, I therefore think Roux is ideally suited for
             | teaching to complete beginners. Unfortunately, nobody has
             | done it yet.
        
         | 0x1ceb00da wrote:
         | Don't start with algorithms. Figuring out how to solve them is
         | half the fun. If you want to be a speedcuber you could always
         | look up algorithms later but you can't unlearn the algorithms
         | once you learn them.
        
           | BenjiWiebe wrote:
           | Perhaps it worked that way with you, but I'm not smart enough
           | to figure out a 3x3 on my own, and wouldn't have had the many
           | many hours of enjoyment that I did have, if I wouldn't have
           | learned any algorithms.
           | 
           | It's not like memorizing algorithms makes it trivial -
           | there's still recognition/look-ahead and finger tricks to
           | learn, if you want to get faster. And finding the optimal
           | cross (in CFOP method) during the 15 second inspection takes
           | some thinking. I'm bad at that.
        
           | queuebert wrote:
           | Also true with Nethack. I will forever regret reading
           | spoilers before I seriously tried to ascend.
        
           | dhosek wrote:
           | That's a big part of why I've never learned to solve a
           | Rubik's cube. I'd rather learn how to learn how to solve it
           | than memorize an algorithm and I don't really have the
           | time/motivation/interest to learn how to learn how so I
           | haven't bothered.
           | 
           | My son, at age 9, loved learning these kinds of algorithms
           | (he also learned how to solve square roots by hand from a
           | YouTube video and would do random square root calculations to
           | entertain himself, checking his answers against the
           | calculator on my ex-wife's kitchen Alexa).
        
         | zoomablemind wrote:
         | IMO, the firstmost source is your own observations. 3x cube is
         | very tactile, so some moves are just natural.
         | 
         | It helps also to develop some sort of notation for yourself.
         | This way you can track and repeat your moves.
         | 
         | Solving by layers is kinda logical. So solving one side (first
         | layer) is not hard. Then some experimentation with rotation
         | sequences which temporarily break the solved layer/face and
         | then re-assemble it will lead to discovery of moves to swap the
         | edges into the second layer.
         | 
         | The hardest then is to solve the third layer. Again, the
         | notation and observations help charting your way through.
         | 
         | A curious discovery may be about some repeated pattern of moves
         | which may be totally shuffling the cube yet, if continuing it,
         | eventually returns the position to the beginning state. It's
         | kind of a "period".
         | 
         | Have fun.
        
           | Oreb wrote:
           | Solving by layers is logical, it's what most beginners learn,
           | and it is kind of how CFOP (the most popular speedsolving
           | method) works. Nevertheless, it's not what I would recommend.
           | The problem with solving layer by layer is that you are sort
           | of painting yourself into a corner from the beginning. After
           | you have finished the first layer, you can't really do
           | anything without breaking the first layer. Of course it is
           | possible (and necessary) to proceed in a way where you keep
           | breaking and repairing the first layer while progressing with
           | the rest of the cube, but the limited freedom of movement
           | still makes the solution process needlessly complicated, and
           | increases the move count.
           | 
           | In my opinion, it's better to start by solving a part of the
           | cube that still leaves you with a significant amount of
           | freedom of movement without breaking what you have already
           | done. There are several ways to do this. My favorite method
           | (Roux) starts by not making a full layer, but just a 3x2
           | rectangle on one side. This rectangle is placed on the bottom
           | left part of the cube. You still have a considerable degree
           | of freedom, you can turn the top layer and the two rightmost
           | layers without breaking your 3x2 rectangle.
           | 
           | The next step is to build a symmetrical 3x2 rectangle on the
           | lower right side of the cube. This is quite easy to do by
           | just using the top layer and the two rightmost layers, thus
           | avoiding to mess up the left hand 3x2.
           | 
           | After finishing the two 3x2 rectangles (commonly known as the
           | "first block" and the "second block"), the next step is to
           | solve the corners on the top of the cube. This is the only
           | algorithmic step of Roux, you use a number of memorized
           | algorithms. However, the algorithms are shorter and simpler
           | than those for the top layer of a layer-by-layer approach,
           | because the algorithms are allowed to mess up everything
           | along the middle slice (which hasn't been solved yet) and the
           | edge pieces on the top of the cube.
           | 
           | After finishing the top corners, you are still free to move
           | the middle slice and the top layer without messing up what
           | you've already done. Fortunately, this is enough for solving
           | (intuitively!) the remaining pieces. You can finish the solve
           | by using only these non-destructive moves.
           | 
           | The Roux method, therefore, allows you to keep the maximum
           | degree of freedom of movement (without destroying what's
           | already been solved) all the way until the end. This is what
           | allows it to have a very low move count, and what's makes it
           | easy to learn. It also gives you a lot of creative
           | opportunities compared to CFOP and other layer-by-layer
           | methods. Because of the increased freedom, there are more
           | ways of doing things, and bigger scope for clever shortcuts,
           | especially when building the first and second blocks.
        
       | boneitis wrote:
       | (Snark warning, but even more than that, I find myself amused and
       | amazed by the overall story)
       | 
       | Ah, yes. Ruwix, the beloved Rubik's cube tutorial site that
       | abused and cheated their way to the top of SEO rankings[0] in
       | ethically dubious manner by directly victimizing end-users.
       | 
       | [0]: https://news.ycombinator.com/item?id=27427330 ("How I
       | uncovered a black-hat SEO scam")
        
         | spiderice wrote:
         | Wow.. that was a fun rabbit hole to go down. Makes me wish HN
         | wasn't pushing a bunch of traffic to them this morning.
        
       | zuminator wrote:
       | I've read that the minimum number of moves for solving a 3x3x3
       | cube in its most scrambled state ("God's number") is just 20
       | moves, and this was verified through brute force search. I'm
       | uncertain as to whether there is an algorithm for solving an
       | arbitrarily scrambled cube in just 20 moves, or if it's just
       | known that it is possible to be solved in 20 moves, but probably
       | the latter. Anyway, I can't seem to find a corresponding God's
       | number for the 4x4x4 cube but it seems perhaps the lower bound is
       | in the 30-40 move range. I not a cuber (?) by any means so I
       | don't know if there's any sort of formula to even approximate the
       | lower bound for solving successively higher level cubes, but if
       | there is, I'd be very curious to know what the approximate God's
       | number is for this 34x34x34 beast.
       | 
       | Anyway if we were to go with just a very naive guess that each
       | higher level takes 1.5x the moves of the previous level so
       | 3x3x3=20, 4x4x4=30, 5x5x5=45 and so on, that would yield
       | 34x34x34= 5,752,532 moves (or 5,817,104 if you round up 1 at
       | every fractional result), which at a second per move, would take
       | over 2 months to solve. I suspect that in practice, any
       | algorithmic means to solve such a cube would take somewhat
       | longer, so much so that a thoroughly scrambled cube might never
       | be unscrambled.
        
         | fanf2 wrote:
         | The web site for God's Number is http://www.cube20.org/
        
         | incognito124 wrote:
         | You mean the maximum number of moves?
        
           | mr_mitm wrote:
           | The way I read it was that it's the maximum minimum number of
           | moves.
        
         | marsten wrote:
         | Based on the bounds discussed at
         | https://old.reddit.com/r/Cubers/comments/8chfuu/i_found_a_ge...
         | it appears that a 34x34x34 cube can be algorithmically solved
         | in under 100,000 moves.
         | 
         | Maximum number of moves scales as n^2.
        
           | zuminator wrote:
           | Wow that's incredible, far less than I imagined. Thanks!
        
         | Jabbles wrote:
         | > God's number for the 4x4x4 cube
         | 
         | it has been proved only that the lower bound is 31, while the
         | most probable value is considered to be 32
         | 
         | https://oeis.org/A257401
        
       | ambyra wrote:
       | This is strange, probably not fun to play. I think an exploded
       | view (t shape) on the computer would be cool.
        
       | SirMaster wrote:
       | Why are the corners so big?
        
         | nachox999 wrote:
         | they wanted to make sure nothing could cut in
        
         | NeoTar wrote:
         | Each corner piece needs to make contact with the core.
         | 
         | Consider when the top layer is rotated 45 degrees relative to
         | the layer below. The corner is now about 0.707 units from the
         | centre of the face, but the layer below only extends 0.5 units
         | out from the centre.
         | 
         | If the corner pieces were smaller than about 0,207 units it
         | would become disconnected from the cube as a whole.
         | 
         | So, any cube larger than (I believe) the 5 by 5 either needs to
         | have bulging faces, or have the edge/corner pieces larger than
         | the others.
        
           | SirMaster wrote:
           | Hmm, it looks like even a 7x7x7 doesn't need to have much. I
           | guess it has a tiny amount larger edge and corner pieces
           | though...
           | 
           | https://www.amazon.com/Shengshou-7x7x7-Cube-Puzzl-
           | black/dp/B...
        
             | NeoTar wrote:
             | You are correct, the 7 x 7 x 7 is the minimum where a
             | perfect cube of cubes is impossible. The Wikipedia article
             | shows the issue with the corner cubes.
             | 
             | Apparently the 7-cube bulges slightly which helps to hide
             | that the larger sized edges / corners
             | 
             | https://en.m.wikipedia.org/wiki/V-Cube_7
        
       | dllu wrote:
       | 3D printing technology is amazing now. I used to struggle with my
       | ABS prints warping 12 years ago with a PP3DP --- I couldn't even
       | print a giant 3x3x3 rubik's cube that worked. Now there are lots
       | of 3D printers that are essentially just zero configuration and
       | everything works out of the box. I even printed a lens mount for
       | my camera and it came out quite well aligned. So it is very nice
       | to see some regular consumer 3D printers being good enough for a
       | functional 34 x 34 x 34 cube.
        
       | ksymph wrote:
       | Small error: Oskar van Deventer's 17x17 is at 2009 in the
       | timeline, but the description says 2011.
        
       | corry wrote:
       | A few months ago I learned to solve the classic 3x3x3 using the
       | beginner's method [0]. Basically, you memorize a set of
       | algorithms based on the current state of the cube and what
       | overall stage of solving you're at (you first solve the white
       | layer, then the middle layer, then the final layer).
       | 
       | What's funny is that I feel no compulsion to learn other methods,
       | no compulsion to get faster at it, no compulsion to move up to
       | larger cubes like 4x4x4 etc.
       | 
       | I just find it soothing and meditative. In fact, doing a few
       | cubes has replaced some amount of doom-scrolling for me. Hard to
       | describe exactly. Scratches some hand-eye / brain-motor itch.
       | 
       | [0] This is the guide I used:
       | https://assets.ctfassets.net/r3qu44etwf9a/6kAQCoLmbXXu29TTuA...
        
         | Snacklive wrote:
         | Yes, i understand perfectly this is exactly what i do with my
         | cube, it is sitting in my desk and i give it a few solves
         | daily, it really helps to keep my mental in a good state.
         | 
         | I will probably buy another this time stickerless to not worry
         | about them deteriorating over time
        
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