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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,387

Then let me wish her a Happy Birthday, that might help.

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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That is a good idea.

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'Humanity is still kept intact. It remains within.' -Alokananda

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,387

Is she happy now?

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

**Online**

Why won't she be? But where is your Happy Birthday post?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'Humanity is still kept intact. It remains within.' -Alokananda

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,387

Happy Birthday, Alokananda!

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

**Online**

Thank You, bobbym

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'Humanity is still kept intact. It remains within.' -Alokananda

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,387

That would cheer me up.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

**Online**

Agnishom wrote:

Oops!

how do I compute the last three digits of 2014C1+2014C3+2014C5+...+2014C2013 by hand?

Consider the question: In how many ways can you select things from a collection of 2014 things?

This is equivalent to 2014C1 + 2014C2 + 2014C3 + .. 2014C2014

For each doll you have, 2 choices. To select it or not, so there are 2^2014 ways.

Now, for only odd number of dolls:

Half of those cases we selected odd number of dolls

This is equivalent to asking in how many cases you are choosing the odd terms.

Clearly the answer is 2^2013

bobbym wrote:

Algebra is Combinatorics, Combinatorics is Algebra

*Last edited by Agnishom (2014-10-04 01:08:52)*

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'Humanity is still kept intact. It remains within.' -Alokananda

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