Solve this congruence equation

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Phlembac Adib Hasan
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Solve this congruence equation

Unread post by Phlembac Adib Hasan » Wed Jan 23, 2013 10:32 pm

Find all positive integers n such that $2^{n-1} \equiv -1 \pmod{n}$.
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Phlembac Adib Hasan
Posts: 1016
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Re: Solve this congruence equation

Unread post by Phlembac Adib Hasan » Thu Jan 24, 2013 12:20 pm

Nobody interested? Well I'm giving a hint.
Think about order and Fermat's little theorem.
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zadid xcalibured
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Re: Solve this congruence equation

Unread post by zadid xcalibured » Thu Jan 24, 2013 6:18 pm

Still not interested. $SIGH$
btw,Happy Birthday.

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