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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,937

I did use my function:

Input:

```
list : [6,6,6,6]$
expand(CombOGF(list)/6^4);
```

Output:

```
x^24/1296+x^23/324+(5*x^22)/648+(5*x^21)/324+(35*x^20)/1296+(7*x^19)/162+(7*x^18)/108+(29*x^17)/324+(149*x^16)/1296+(5*x^15)/36+(103*x^14)/648+(14*x^13)/81+(77*x^12)/432+(14*x^11)/81+
(103*x^10)/648+(5*x^9)/36+(149*x^8)/1296+(29*x^7)/324+(7*x^6)/108+(7*x^5)/162+(35*x^4)/1296+(5*x^3)/324+(5*x^2)/648+x/324+1/1296
```

And the term with exponent 20 has the coefficient of 35/1296.

*Last edited by anonimnystefy (2012-04-30 08:00:36)*

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: 97,297

Now supposing 2 die had faces of 2,4,6,8,10,12 and 2 other die had faces of 1,3,5,7,9,11.

All four die are thrown once. What is the probability of them summing to 20 or more?

**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: 15,937

493/648?

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: 97,297

That 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.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,937

Thought so.

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: 97,297

What did you have a problem with?

**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: 15,937

Altering the code to acompany the numbers on the dice.

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: 97,297

There is a rather succinct method to do that in mathematics. It is called

summation notation. It is perfect. It is implemented in Maxima. That is why I suggested you use

math commands to do math tasks.

**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: 15,937

I did use the summation un a part of my code.

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: 97,297

But you did not use parameters with the summation. Then the code is simple, fast and

complete.

**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: 15,937

Iwill try today you function. But I do not like that I have to type everything agin to make a GF for more dice.Here for 100 dice,I could just make code (agin to your disliking) to make me a list of 100 omes. I just put that list into my function and I am done.

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: 97,297

You are misunderstanding my reasoning. It is not an arbitrary decision. It is not bobbym's

function.

1) Built in functions are faster and use less memory than procedural code.

2) Your function can not handle gf's that increment by more than one. Remember yours

did not get the right answer.

3) Supposing you were throwing 10 million die? Do you want to create a list of

10 million numbers? My function does not grow in size when the problem does

**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: 15,937

The first one is right.

The second one is not correct. I made a new one that uses the parameter n for the increment.

Third one is also right.

4)Is yyour function applicable to dice with more sides?

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: 97,297

Of course!

About 2) Your new function is probably larger, uses more memory and is slightly slower.

In mine it easy to do things like that with no overhead increase. Bet it took you a couple of hours to

add your addition. In mine additions are part of the notation.

**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: 15,937

Nope,just one multiplication by n.

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: 97,297

But I hope you can see that the one I want you to use is smaller.

**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: 15,937

Yes,I will try your way.

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: 97,297

Is there something done?

**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: 15,937

Not yet. No access to Maxima yet.

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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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,937

Hi bobbym

Check out this link:A pdf file on GFs in counting problems

It isn't very much,but does explain some crucial things.

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: 97,297

Hi anonimnystefy;

I disagree it is quite good.

**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: 15,937

Who said it wasn't good. Everything that you need is in there. Maybe a few more solved harder examples and it would be even better.

Hay,I found somewhere a GF for partitions of a number but I disagree with the formula. Could you post the partition GF you think is right?

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: 97,297

Depends on what you are partitioning.

**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: 15,937

Partitions of a number.

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: 97,297

Which 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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