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## #1 2016-12-19 14:35:19

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
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### Ten Cool Experimental Mathematics Problems

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #2 2016-12-19 14:37:11

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

### Re: Ten Cool Experimental Mathematics Problems

Those are the 100 digit problems posed a few years ago.

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.

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## #3 2016-12-19 14:40:50

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

Can you solve them all?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #4 2016-12-19 14:41:47

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

### Re: Ten Cool Experimental Mathematics Problems

You are joking of course?!???!!!!!!

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.

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## #5 2016-12-19 14:46:09

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #6 2016-12-19 14:48:32

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

### Re: Ten Cool Experimental Mathematics Problems

Folkmar, unless I am mistaken was on one of the teams that got all ten right.

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.

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## #7 2016-12-26 16:00:35

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

Bouncing Photons (Part II)

Steven created a problem inspired by one of those. It is not very hard, though.

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #8 2016-12-26 17:56:34

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

### Re: Ten Cool Experimental Mathematics Problems

You solved it?

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.

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## #9 2016-12-26 18:47:12

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

Yes.

The person below did not expect that

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #10 2016-12-26 18:51:13

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

### Re: Ten Cool Experimental Mathematics Problems

Dost thou consider thyself wise in the ways of programming? Art ye ready for a challenge that hath stumped the mightiest?

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.

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## #11 2016-12-26 19:49:36

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

Count Dooku wrote:

Good. Double the pride, double the fall.

No, I do not consider myself wise, because of the above principle. But I will look at your problem and try it.

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #12 2016-12-26 19:56:33

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

### Re: Ten Cool Experimental Mathematics Problems

If thou art diligent and wise, O stranger, compute the number of cattle of the
Sun, who once upon a time grazed on the fields of the Thrinacian isle of Sicily,
divided into four herds of different colours, one milk white, another a glossy black,
a third yellow and the last dappled. In each herd were bulls, mighty in number
according to these proportions: Understand, stranger, that the white bulls were
equal to a half and a third of the black together with the whole of the yellow,
while the black were equal to the fourth part of the dappled and a fifth, together
with, once more, the whole of the yellow. Observe further that the remaining
bulls, the dappled, were equal to a sixth part of the white and a seventh, together
with all of the yellow

That problem was supposedly posed by a god, mine is somewhat easier.

There are 3 kegs of water. The first keg has 1 liter, the second keg has 2 liters and the third keg has 3 liters of water in it. Each day our traveller picks one keg at random with each keg having the same chance of being picked and takes and drinks one liter of water from it. When he empties a keg he throws it away. When he is left with one keg he records the amount of water in it. What is the expected amount of water remaining in that last keg?

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.

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## #13 2016-12-27 00:49:58

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

The answer is (125/72) according to RIES and I have verified that in two ways.

Using a simulation:

``````from random import choice

def simulate(kegs):
while len(kegs) > 1:
n = choice(range(len(kegs)))
kegs[n] -= 1;
if kegs[n] == 0:
del kegs[n]
return kegs[0]

ans = sum((simulate([1,2,3]) for i in range(1000000)))/1000000``````

and actually evaluating the probability tree:

``````import Data.List

type Keg = Float	-- Capacity Water
type State = [Keg]

rots :: [a] -> [[a]]
rots xs = init (zipWith (++) (tails xs) (inits xs))

calculate :: State -> Float
calculate kegs = go 0.0 1.0 kegs
where
go :: Float -> Float -> State -> Float
go e p [w]	= e + p*w
go e p kegs			= foldr (\st e' -> go e' p' st) e newStates
where
newStates = [ f s | s <- (rots kegs) ]
f (1.0:ks) = ks
f (w:ks) = (w-1):ks
p' = p/(fromIntegral \$ length newStates)

ans = calculate [1,2,3]``````

Last edited by Agnishom (2016-12-27 01:07:50)

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #14 2016-12-27 06:55:21

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

### Re: Ten Cool Experimental Mathematics Problems

You do not need RIES to rationalize a fp but very good, you solved the problem.

How high can your tree go? Can you do 2 to 10 kegs? A ten keg problem would be 1,2,3,4,5,6,7,8,9,10 liters per bottle.

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.

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## #15 2016-12-27 13:08:09

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

What is an fp?

I can only do upto 4 with the tree program. It grows rapidly

Last edited by Agnishom (2016-12-27 13:08:34)

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #16 2016-12-27 13:23:40

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

### Re: Ten Cool Experimental Mathematics Problems

Stands for floating point.

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.

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## #17 2016-12-27 13:35:02

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

1.9035132137345392

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #18 2016-12-27 13:39:04

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

### Re: Ten Cool Experimental Mathematics Problems

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.

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## #19 2016-12-27 13:53:22

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

Post #17 is what I have.

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #20 2016-12-27 13:56:57

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

### Re: Ten Cool Experimental Mathematics Problems

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.

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## #21 2016-12-27 13:57:53

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

How do you get it?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #22 2016-12-27 13:59:22

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

### Re: Ten Cool Experimental Mathematics Problems

By copy and paste.

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.

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## #23 2016-12-27 14:09:41

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

What is that again?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #24 2016-12-27 14:14:00

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

### Re: Ten Cool Experimental Mathematics Problems

I copied and pasted.

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.

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## #25 2016-12-27 14:45:15

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,843
Website

### Re: Ten Cool Experimental Mathematics Problems

In other words, you have more digits than I do.

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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