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#201 2012-05-02 10:40:53

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Wow,they totally missed 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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#202 2012-05-02 10:42:33

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

Missed what?


I will post another problem in here.


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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#203 2012-05-02 10:43:40

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

They missed your post.

I am looking forward to the problem.


“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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#204 2012-05-03 02:38:40

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

When can I expect the problem?


“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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#205 2012-05-03 04:42:44

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

A game is played. You roll a red die and then roll as many green die as the number on the red die. What is the probability of the sum of the green die equalling 17?

Is this a generating function problem?


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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#206 2012-05-03 04:44:35

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

My first guess would be a no,but I will have to look at it a little.


“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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#207 2012-05-03 05:19:01

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Maybe the coeff of x**17 in ((x+x**2+x**3+x**4+x**5+x**6)+ (x+x**2+x**3+x**4+x**5+x**6)**2+(x+x**2+x**3+x**4+x**5+x**6)**3+ (x+x**2+x**3+x**4+x**5+x**6)**4+(x+x**2+x**3+x**4+x**5+x**6)**5+ (x+x**2+x**3+x**4+x**5+x**6)**6)/6?

Last edited by anonimnystefy (2012-05-03 05:22:15)


“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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#208 2012-05-03 05:26:29

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

That is almost correct except there is an error. Do you see 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.

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#209 2012-05-03 05:30:17

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Oh,yeah,I wasn't really sure about that division by six. Thinking about it again it seems logical not to include it.

Last edited by anonimnystefy (2012-05-03 05:30:40)


“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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#210 2012-05-03 05:32:29

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

Without that 6 down there we would have a combinatorics problem but this is a probability problem.


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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#211 2012-05-03 05:33:42

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Well,I need to divide by what we get when we sub x=1.

Last edited by anonimnystefy (2012-05-03 05:34:09)


“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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#212 2012-05-03 05:36:18

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

But as it stands with or without that 6 the answer is not correct.


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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#213 2012-05-03 05:37:18

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Is the GF okay?


“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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#214 2012-05-03 05:38:28

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

We have not even established the need for one but that one is 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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#215 2012-05-03 05:40:05

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Why is it not 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

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#216 2012-05-03 05:42:14

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

It needs some work done on 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.

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#217 2012-05-03 05:43:46

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Anything besides mulirplying by a constant?


“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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#218 2012-05-03 05:45:16

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

I would think that multiplying by any constant would not fix it. But that is another question.


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

#219 2012-05-03 05:47:41

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Couod you tell me where the problem is?


“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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#220 2012-05-03 05:48:18

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

Do you have access to a CAS right now?


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

#221 2012-05-03 05:50:11

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Not right now. Phone. hmm

Maybe I could try getting on my laptop,but that doesn't seem probable. At least not till 10.


“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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#222 2012-05-03 06:01:51

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

Remember any answer is not any good unless it is arrived at in two different ways. Two different directions, then you have some certainty.

I know of a forum filled with olympiad hopefuls. They try to solve combinatoric problems. They post the wrong answer, why? Because they did not check it to see if it was possibly correct. Computers and combinatorics are married. When you use them together you will be more accurate than those who do not.

I think if you would have expanded that gf you would have seen that it can not be right. We would not be going back  and forth right now. In short, we would be going faster.


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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#223 2012-05-03 06:10:00

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

I just had an idea! Should those be EGFs instead of OGFs?


“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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#224 2012-05-03 06:10:53

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,582

Re: Generating Functions

Does order count? Is 5 + 3 + 2 different than 3 + 5 + 2?


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

#225 2012-05-03 06:32:55

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Generating Functions

Nope. Isn't that why it should be an EGF?


“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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