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## #26 2012-08-31 07:00:53

MathsIsFun

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### Re: Combinations and Permutations "Rules"

It may simply have run out of time ... I know it took a while on my PC.

Try a slightly smaller one and see if it works

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

## #27 2012-08-31 07:50:14

anonimnystefy
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### Re: Combinations and Permutations "Rules"

Hi MIF

It works for a,a,b,c,d. But, functioning for inputs smaller than 10 input characters isn't very practical. Maybe you can use some other method for calculating their number (using e.g. a script written in a mathematical package).

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #28 2012-08-31 08:07:14

bobbym

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### Re: Combinations and Permutations "Rules"

Hi MIF;

It may simply have run out of time ... I know it took a while on my PC.

Yes, it takes some time on mine too. It seems to be working fine for smaller ones.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #29 2012-08-31 08:10:39

anonimnystefy
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### Re: Combinations and Permutations "Rules"

What input did you take, bobbym?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #30 2012-08-31 08:12:55

bobbym

Online

### Re: Combinations and Permutations "Rules"

Hi;

Where?

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #31 2012-08-31 08:18:21

anonimnystefy
Real Member

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### Re: Combinations and Permutations "Rules"

#### bobbym wrote:

Yes, it takes some time on mine too.

What did you enter as an input (which letters) that gave the slow output?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #32 2012-08-31 08:22:35

bobbym

Online

### Re: Combinations and Permutations "Rules"

Hi;

Post #17.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #33 2012-08-31 08:31:36

anonimnystefy
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### Re: Combinations and Permutations "Rules"

"m,a,t,h,e,m,a,t,i,c,s"? I get the results pretty fast for that one.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #34 2012-08-31 08:33:20

bobbym

Online

### Re: Combinations and Permutations "Rules"

Hi anonimnystefy;

What settings and what answer did you get?

I use:

11
5
Yes
No

see the first drawing in post #17.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #35 2012-08-31 11:12:51

anonimnystefy
Real Member

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### Re: Combinations and Permutations "Rules"

11
5
No
No

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #36 2012-08-31 14:01:55

bobbym

Online

### Re: Combinations and Permutations "Rules"

Hi;

That is not the same problem.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #37 2012-08-31 17:41:48

MathsIsFun

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### Re: Combinations and Permutations "Rules"

The calculations are done on your own PC, so results may vary.

And so it is hard for me to write a program that will finish within the "timeout" that is imposed by Flash.

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

## #38 2012-08-31 17:49:14

bobbym

Online

### Re: Combinations and Permutations "Rules"

Hi MathsIsFun;

No problem. It works for the smaller problems that I have tried on it so far.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #39 2012-08-31 22:07:19

anonimnystefy
Real Member

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### Re: Combinations and Permutations "Rules"

Hi bobbym

You are right. It takes much more time and it comes out empty.

Hi MIF

I would suggest that for very large output (more than 10^7 possibilities), you do not show the whole output, just the number of possibilities.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #40 2012-08-31 23:21:53

bobbym

Online

### Re: Combinations and Permutations "Rules"

Hi;

10^7 is a little bit too large. The above problem only has 13000 permutations. Maybe 10^5 is better.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #41 2012-08-31 23:29:27

anonimnystefy
Real Member

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### Re: Combinations and Permutations "Rules"

Either way, it should skip the printing when the number is large.

How did you calculate the number of the possible combinations?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #42 2012-08-31 23:31:46

bobbym

Online

### Re: Combinations and Permutations "Rules"

I didn't. I counted the number of permutations.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #43 2012-08-31 23:39:15

anonimnystefy
Real Member

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### Re: Combinations and Permutations "Rules"

What permutations?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #44 2012-08-31 23:41:29

bobbym

Online

### Re: Combinations and Permutations "Rules"

The problem in post #17 is a permutation.

As you were taught, you try not to work on a problem that you do not already know the answer to. Remember back engineering? You work from the answer to the question, filling in the details.

Normally to do that I would have just counted them up first. But here MIF already does that with his program so you should use what to get the answer?

GF's of course!

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #45 2012-09-01 00:13:54

anonimnystefy
Real Member

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### Re: Combinations and Permutations "Rules"

When you choose a number of objects out of a larger set of objects, those can be only combinations or variations, not permutations.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #46 2012-09-01 00:19:49

bobbym

Online

### Re: Combinations and Permutations "Rules"

Did you look at post #17? When order counts we are talking about a permutation.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #47 2012-09-01 00:23:03

anonimnystefy
Real Member

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### Re: Combinations and Permutations "Rules"

No, when order counts, it is a variation.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #48 2012-09-01 00:30:34

bobbym

Online

### Re: Combinations and Permutations "Rules"

Hi;

You will notice that in this exact type of problem he calls it an arrangement or permutation.

Anyways, it is calculated in the same way.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #49 2012-09-01 00:33:55

anonimnystefy
Real Member

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### Re: Combinations and Permutations "Rules"

Just because he calls it that, doesn't mean it should be called that way.

I can't seem to calculate those using GFs.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #50 2012-09-01 00:39:35

bobbym

Online

### Re: Combinations and Permutations "Rules"

http://en.wikipedia.org/wiki/Permutatio … binatorics

Post #17 is similar to a mississippi problem, which is definitely a permutation.

I can't seem to calculate those using GFs.

Well of course you can not if you call it a variation. There are ogf's for combinations and egf's for permutations.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.