For discussing Olympiad Level Number Theory problems
Rafe
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a,b,c,d,.....is a sequence.the number of factors of a,b,c,d,....is 2,3,4,5,....find the minimum value of a in natural number
Last edited by Rafe on Sat Jan 19, 2013 2:38 pm, edited 1 time in total.

nafistiham
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Rafe wrote:$a,b,c,d,.....$ is a sequence.the number of products of $a,b,c,d,....$ is $2,3,4,5,....$ find the minimum value of a in natural number
How can a natural number have a limited number of products ?
Are you talking about factors ?
$\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0$
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Prosenjit Basak
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Rafe wrote:a,b,c,d,.....is a sequence.the number of factors of a,b,c,d,....is 2,3,4,5,....find the minimum value of a in natural number
Factor means prime factor or only factor?
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Rafe
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i mean all factors.such as 8 has 4 factors

Fahim Shahriar
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$2,4,8,16.....,2^n$

$2^n$ has $(n+1)$ factors.
Name: Fahim Shahriar Shakkhor
Notre Dame College

nafistiham
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$2,4,8,16.....,2^n$

$2^n$ has $(n+1)$ factors.
I think that is it. And, so, $a=2$

Prosenjit Basak
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I don't think so.You said $a=4$.But $4$ has $3$ factors. But in the question Rafe said $a$ has $2$ factors. So $a$ can't be $4$. I think Fahim Bhai may be correct.
Yesterday is past, tomorrow is a mystery but today is a gift.

nafistiham
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Prosenjit Basak wrote:I don't think so.You said $a=4$.But $4$ has $3$ factors. But in the question Rafe said $a$ has $2$ factors. So $a$ can't be $4$. I think Fahim Bhai may be correct.
...... that really was a lousy mistake.
$\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0$
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.

Prosenjit Basak
Posts: 53
Joined: Wed Nov 28, 2012 12:48 pm