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<<Problem Attached>>

'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'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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**stapel****Member**- Registered: 2006-07-22
- Posts: 15

For other users: The text of the tiny image is as follows:

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Thank You -_-"

'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'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

Hi Agnishom;

I am getting 17.

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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I do not know the answer.

But please do tell about how you did this

'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'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

Hi;

The probability is 2 / 15 , so a + b = 17.

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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Yes, I agree

How did you know that it is 2/15?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

Hi;

where r is the number of chords. Plug in 4 and you get 2 / 15.

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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**zetafunc.****Guest**

Where did you get that formula from?

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

Hi;

It was got from some combinatorial reasoning and some experimental mathematics. I am also working on another method.

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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So, what is the reasoning behind it?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

As you know any probability can expressed as success / ( success + failure).

That allows us to break the problem down into 2 sub problems.

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

Hm, how'd you get that formula?

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.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

Post #12 outlines the method I used. Did you understand what I meant?

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

Yes. But, I still do not know how you got that...

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.

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Maybe you are using something like a case study? Or a recurrence relation?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

The job is done if it is correct in two steps. The denominator is done first.

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

How'd you get the denominator?

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.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

If you call the first point A there are n-1 lines that can drawn from that point. From the second point there are n-3 lines from the third point there are n-5 lines etc.

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

How does that give you (n+1)! ?

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.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

There are cancellations with the the numerator.

The numerator is the world famous Catalan Numbers!

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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I really didn't understand

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

I am working on something simpler than the first idea. It should be clearer.

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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But I like the Idea, please make it clearer

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,157

The denominators are easy, the numerators are the Catalan numbers. The author of this idea noticed that the solution is the same as the bracket matching problem. So, I used that.

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.**

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