count it

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Rafe
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count it

Unread post by Rafe » Sun Jan 06, 2013 4:15 pm

$\frac{n+y}{n}$ is an integer for some integer value of $n$ while $y$ is an integer.find the summation of the value of all $n$
Last edited by sourav das on Sun Jan 06, 2013 8:30 pm, edited 1 time in total.
Reason: LaTeXed

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SANZEED
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Re: count it

Unread post by SANZEED » Sun Jan 06, 2013 10:24 pm

Write $\frac{n+y}{n}=1+\frac{y}{n}$ so $n$ must divide $y$. Thus sum of the values of all $n$ is actually the sum of divisors of $y$. :|
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Phlembac Adib Hasan
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Re: count it

Unread post by Phlembac Adib Hasan » Mon Jan 07, 2013 11:32 am

@ SANZEED, Rafe has said $n\in Z$, not $n\in N$.
If $a$ divides $y$, then $-a$ also divides $y$. Hence summation of all values of $n$ is $0$.

In my pc, I am not seeing \mathbb characters. Is it happening also to you? If is, then I think the file 'AMSmath.js' has been damaged in this server. We should inform it to Moon Vai immediately.
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*Mahi*
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Re: count it

Unread post by *Mahi* » Mon Jan 07, 2013 2:04 pm

Phlembac Adib Hasan wrote:In my pc, I am not seeing \mathbb characters. Is it happening also to you? If is, then I think the file 'AMSmath.js' has been damaged in this server. We should inform it to Moon Vai immediately.
No, all \mathbb symbols are loading alright in my PC. You might try clearing your jsMath cache.
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Phlembac Adib Hasan
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Re: count it

Unread post by Phlembac Adib Hasan » Tue Jan 08, 2013 1:35 pm

Thanks. It helped.
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