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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

You can see there that a permutations of n elements always contains n elements, and not less.

You can call them variations and still use EGFs. I just cannot remember how to do that.

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: 98,945

anonimnystefy wrote:

You can see there that a permutations of n elements always contains n elements, and not less.

"permutations and combinations" refers to two related problems, both counting possibilities to select k distinct elements from a set of n elements, where for k-permutations the order of selection is taken into account, but for k-combinations it is ignored.

k can be less than n.

If egf's solve permutation problems and they solve this one is it not likely that this is a permutation problem?

If you need to see how to solve them please ask the question in Help Me. I will show you.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

If you can use detergents to clean dishes and to clean your hands, are the two the same thing?

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: 98,945

Hmmm... I use Boraxo, 20 mule team of course. Truthfully, I have never heard that term and do not consider it correct. You know how I feel about jargon. If you need authoritative evidence in addition to the two links provided just let me say that I am considered to be the best combinatoricist on my block. True it is a small block just 4 buildings but still...

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**dodgyg1****Member**- Registered: 2012-09-27
- Posts: 1

Hi guys,

I am new here.Really impressed with the combinations and permutations calculator. Would it be possible for someone to add a rule where if the elements are integers then results are only shown if the sum of the combinations/permutations add up to a given number.

Thanks bin anticipation.

Best regards,

dodgyg1

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,945

Hi dodgyg1;

That is a certain type of partition. There are ways to calculate them.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **Thinking is cheating.**

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