Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,972

And mine wasn't an answer, but a request.

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

Well,your post sounded more like an answer to a question,than a sentence of its own.

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,972

Well, maybe. I can see how it would look.

But you didn't have a question mark on yours, so, obviously, I couldn't have been answering anything, could I?

(That's a rhetorical question, by the way, so it does not require an answer.)

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

You couldn't have been answering anything,but it did look like you did. I couldn't make any sense of it any other way.

Ever learned to solve a Rubik's cube?

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,972

Yes, I can do a Rubik's cube; and make pretty patterns with the pieces.

But it won't surprise you to learn that I do it slowly and try to find efficient moves rather than speed resolving.

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

What about the 4 by 4 and 2 by 2?

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,972

I have a 5 x 5 x 5

I haven't got a complete set of restoring moves for this yet so it takes a while to finish this one.

Never seen a 2 x 2 x 2. Should be able to do that in the dark.

I've also got a octagonal prism version. You have to be careful about the colours as they can fool you.

Back in the '80s we organised a speed competition between schools. Kids were dismantling their cubes, then filing off the rough bits to make them turn faster and coating the surfaces with oil to again improve the turning speed. Best time was somewhere bewteen 60 and 90 seconds. One problem was occasionally a cube would explode showering bits all over the floor.

Our school won the team prize but not the individual prize.

I also like those wood and string puzzles where you have to get a ring off the string etc etc.

I was given a cube (in pieces) made of 4 x 4 x 4 pieces stuck together to make odd shaped bits. You had to re-assemble the cube. I spent ages on it without success. So I wrote a program that coded the pieces and tried them in all possible places, rejecting when a piece had nowhere to go.

I set it running and after a bit stopped it to see how far it had got. I estimated it would take longer than the expected age of the Universe to go through all the possibilities so I gave up that method. My brother-in-law came to stay and did it in an hour. Grrrr!

Bob

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

I can't wait to get a 5x5x5.I have seen in person all sizes from 2x2x2 to 5x5x5.The 2x2x2 is not as naive as you would think,but it can be solved like a 3x3x3.

While watching the online tutorials for the 5x5x5,I thought it was simpler than the 4x4x4.When I tried them out on Friday,I found out it was in fact vice versa.I got my 4x4x4 on the same day in a local store.I was very surprised they hold 4x4x4 and they even told me that they might order new 5x5x5's this week.I can't wait to find out if they actually ordered them.Then I will need just the 2x2x2 to finish the set.

I would also like to get my hands of one of those Teramynx and Rubik's dodecahedrons.They look very cool,but I don't think there are any in our local stores,but there might be ones in Belgrade.I will try to look them up,so I can get them if I go there any time soon.

There are many other Rubik's cube type products,but I really like those 5 (excluding the 2x2x2).

Oh,and,here's a useful youtube video for the 5x5x5:Tutorial for solving the 5x5x5 Rubik's cube (part 1) by MeMyselfAndPi

Stefy

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

Oh,btw,here's an algortihm for your 5x5.

2L 2R 2Uu 2L 2R 2Uu 2L 2R 2D 2L 2R 2U 2l 2r 2Uu 2l 2r 2Uu 2l 2r 2d 2l 2r 2u

Using the standard 5x5 Rubik's cube notation.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

**New Problem:**

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

Hi bobbym

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

You have me at a disadvantage. I can not see any of your proof.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Is it equally invisible?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

To you yes. It will become visible as soon as I can make it such,which will be today.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Okay and please be sure to prove your upper bound also.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

Actually,I find the bound directly. That automatically implies an upper bound.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

How?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

Are you kidding me?

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Nope, some of the methods do not always work.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

Can you find an example for which having an upper bound doesn't imply having an upper bound?

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline