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**rajinikanth0602****Member**- Registered: 2012-06-30
- Posts: 16

(1/x)+(1.3/xsqr)+(1.3.5/xcube)+.........

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Rajnikanth will always challenge

Bharat mahan hain kiun ki ish desh me Rajnikanth hai

'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: 86,364

Hi rajinikanth0602;

Welcome to the forum. I have latexed what I think your question is:

**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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**rajinikanth0602****Member**- Registered: 2012-06-30
- Posts: 16

i will challenge that i will give 7000 rupees for solving dis problem or any important information about that sequence or range of that sequence

*Last edited by rajinikanth0602 (2012-07-02 02:02:26)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

Hi rajinikanth0602;

Save the rupees but that sum diverges.

**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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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,522

Hi bobbym

Is it possible to get a GF of it? I think I have something, but now I am even more unsure of 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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

Hi;

I do not know the answer to that. What I do know is that I have seen that sum before. It is an asymptotic sum. They usually diverge, this one is no different.

**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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**rajinikanth0602****Member**- Registered: 2012-06-30
- Posts: 16

plz bobby sir give any information about it

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

Hi rajinikanth0602;

You can call me bobbym here. That is close to my name.

At present, all I know is that it diverges. I do not have anything else. If I get something I will definitely post it for you.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**rajinikanth0602****Member**- Registered: 2012-06-30
- Posts: 16

thank u for ur wonder full replies and i had never saw the sites like this that will take care of every ones problems

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

Hi rajinikanth0602;

I guess I should say you are welcome but I have not solved the problem yet.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**rajinikanth0602****Member**- Registered: 2012-06-30
- Posts: 16

watz ur job sir

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

Hi;

Currently I am retired.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**rajinikanth0602****Member**- Registered: 2012-06-30
- Posts: 16

watz ur job sir and say any info about you and frm which country

*Last edited by rajinikanth0602 (2012-07-22 03:37:12)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

Hi rajinikanth0602;

As I have said, I am retired due to injuries. That means I no longer work.

When I did work my jobs were math related primarily in numerical analysis, combinatorics, probability and programming mainly.

I am from the United States. I am of southern extraction.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**rajinikanth0602****Member**- Registered: 2012-06-30
- Posts: 16

can u give ur email id im frm india

*Last edited by rajinikanth0602 (2012-07-22 03:41:09)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

Hi rajinikanth0602;

I am sorry but that I can not do on the forum.

Can I ask what you need?

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

Hi rajinikanth0602;

I will do what I can but we can only work through the forum. You can post any problem or most anything right in here. You will receive help and not always from me. There are capable people here.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,522

Hi

See if you can use this:

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

Hi;

It is questionable that you will be able to move the y^2 through the Sigma like that. Or maybe you can. What do you get for an answer?

It seems simplest to me to just prove that the numerator of the summand is larger than the denominator. Then you would be adding an infinite number of terms all greater than 1. Terms that are never getting smaller. This looks like it can be done by induction.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,522

Hi bobbym

S(sqrt(x)) is the same as the sum above. I just want a closed form. Like 1/(1-x) is the EGF for:

even though the sequence doesn't converge.

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

How can you get a closed form? The upper index of summation is not a variable. Either it sums to some constant or it diverges.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,522

Upper index of summation?

Here lies the reader who will never open this book. He is forever dead.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,364

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,522

What about it?

Here lies the reader who will never open this book. He is forever dead.

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