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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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## #202 2012-05-02 10:42:33

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

### Re: Generating Functions

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

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## #204 2012-05-03 02:38:40

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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## #205 2012-05-03 04:42:44

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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## #207 2012-05-03 05:19:01

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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## #208 2012-05-03 05:26:29

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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## #210 2012-05-03 05:32:29

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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## #212 2012-05-03 05:36:18

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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## #214 2012-05-03 05:38:28

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

### 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.
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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## #215 2012-05-03 05:40:05

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

### Re: Generating Functions

It needs some work done on 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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## #217 2012-05-03 05:43:46

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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## #218 2012-05-03 05:45:16

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

Offline

## #220 2012-05-03 05:48:18

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

### Re: Generating Functions

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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

### Re: Generating Functions

Not right now. Phone.

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

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## #222 2012-05-03 06:01:51

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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## #224 2012-05-03 06:10:53

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,149

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

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

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

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