BOMC-2012 Test Day 2 Problem 2

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*Mahi*
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BOMC-2012 Test Day 2 Problem 2

Unread post by *Mahi* » Wed Apr 11, 2012 11:10 pm

Find all finite sets $S$ of nonnegative integers with the property that for any $m,n\in S$ we have $|m-n+1|\in S$.
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shehab ahmed
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Re: BOMC-2012 Test Day 2 Problem 2

Unread post by shehab ahmed » Wed Apr 11, 2012 11:12 pm

My answer was all finite sets with first $n$ odd natural numbers.
Last edited by sourav das on Thu Apr 12, 2012 1:21 am, edited 2 times in total.
Reason: Posted in wrong topic, so moved.

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Re: BOMC-2012 Test Day 2 Problem 2

Unread post by nafistiham » Thu Apr 12, 2012 1:11 am

Same here. :D
\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
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Re: BOMC-2012 Test Day 2 Problem 2

Unread post by Phlembac Adib Hasan » Thu Apr 12, 2012 11:19 am

Me too. :D :D
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Nadim Ul Abrar
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Re: BOMC-2012 Test Day 2 Problem 2

Unread post by Nadim Ul Abrar » Thu Apr 12, 2012 1:07 pm

yeeeesssss ,... ME Too ... :D
$\frac{1}{0}$

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Re: BOMC-2012 Test Day 2 Problem 2

Unread post by nafistiham » Sat Apr 14, 2012 11:31 pm

In these type of problems, trial and error with small integers help a lot to guess out the possible solution and advance toward it with logic. ;)
\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.
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CSE Dept. SUST -HSC 14'
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