PROBLEM NO.51 (B0MC-2,DAY-5)

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SANZEED
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PROBLEM NO.51 (B0MC-2,DAY-5)

Unread post by SANZEED » Wed Apr 04, 2012 11:04 pm

Determine all positive integers $k$ such that
\[\frac{\tau (n^{2})}{\tau (n)}=k\]
for some $n$
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SANZEED
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Re: PROBLEM NO.51 (B0MC-2,DAY-5)

Unread post by SANZEED » Wed Apr 04, 2012 11:36 pm

Hint:
$k$ must be odd.
A general solution can be derived using the fact that every natural number can be written in the following form:\[2^{k}\times (2m+1)\]for some integer $k,m$.
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Re: PROBLEM NO.51 (B0MC-2,DAY-5)

Unread post by sm.joty » Fri Apr 06, 2012 8:19 pm

may be $n=k=1$ :geek:
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Re: PROBLEM NO.51 (B0MC-2,DAY-5)

Unread post by SANZEED » Fri Apr 06, 2012 11:36 pm

No, for all odd $n$,\[\tau (n)\] divides \[\tau (n^{2})\],
note that \[\tau (n)\] means the number of common divisors of $n$ including $1,n$.
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