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#51 2012-04-29 08:53:02

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions


“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

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#52 2012-04-29 08:58:11

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

Better but not right.


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#53 2012-04-29 09:01:29

anonimnystefy
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Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

Oh,I think I get it. We divide by the factorial of the exponent because that is a case when we take "the exponent" number of that letter so we need to divide by "the exponent" factorial.


“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

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#54 2012-04-29 09:05:18

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

Try this one then:

"Murmur", 5 letters.


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#55 2012-04-29 09:08:35

anonimnystefy
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Re: Generating Functions

Hi bobbym

The number of letters really doesn't matter when we are looking for a GF.

Last edited by anonimnystefy (2012-04-29 09:09:14)


“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

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#56 2012-04-29 09:14:16

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

Are you sure?

"MURMURING", create a generating function that counts all possible arrangements of n letters.


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#57 2012-04-29 09:16:11

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

Hi bobbym

Last edited by anonimnystefy (2012-04-29 09:16:41)


“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

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#58 2012-04-29 09:18:51

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

That is very good!

Now how do we get the number of ways for 8 letters out of that?

Taking a break.


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#59 2012-04-29 09:23:19

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

We take the coefficient with x^8.

Ok,see you later!


“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

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#60 2012-04-29 10:51:37

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

Which is what?


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#61 2012-04-29 10:56:09

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

Me getz 9/8. I actually think that it maybe has to be multiplied by 8!


“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

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#62 2012-04-29 10:59:45

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

So what is your answer?


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#63 2012-04-29 11:02:28

anonimnystefy
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Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

I am not sure if it is 9 or 9!/8 or neither. hmm


“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

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#64 2012-04-29 11:05:28

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

The coefficient of x^8 is then multiplied by 8!.


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#65 2012-04-29 11:09:53

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

So 9!/8.


“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

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#66 2012-04-29 11:25:24

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#67 2012-04-29 11:30:56

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

Well that is what I said,isn't it?


“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

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#68 2012-04-29 11:36:29

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

Hi;

You gave a couple of answers. The closest had a maybe in it. You have to post your answer and stand by it.


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#69 2012-04-29 11:46:22

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

anonimnystefy wrote:

So 9!/8.


“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

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#70 2012-04-29 11:47:38

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

Check that again.


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#71 2012-04-29 11:48:38

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

Why?


“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

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#72 2012-04-29 11:49:25

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

Hmmmm? Because it is incorrect.


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#73 2012-04-29 11:56:39

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

It is absolutely the same as your answer in #66.


“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

Online

#74 2012-04-29 16:40:28

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,864

Re: Generating Functions

anonimnystefy wrote:

    So 9!/8.

I thought you were saying that was the coefficient of x^8. Please be a bit more explanatory in your answers. That will prevent misunderstandings. Had you labelled that the final answer or the no of ways then it would have been clear to me.


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

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#75 2012-04-29 16:51:41

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,673

Re: Generating Functions

Ok sorry. So it is correct.


“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

Online

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