Number Theory - divisibility and primes

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future_phd
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Homework Statement


Prove that any integer n >= 2 such that n divides (n-1)! + 1 is prime.


Homework Equations





The Attempt at a Solution


I'm having trouble getting started, I have no idea how to approach this, can someone give a hint on where to begin maybe because I'm just not seeing it.
 
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Assuming that n divides [tex](n-1) \cdot (n-2) \cdots 2 + 1[/tex]. Show that this entails [tex](n-1), (n-2), \cdots 2[/tex] do not divide [tex]n[/tex]. In other words, nothing less than n divides n (except the trivial case).
 
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