Number Theory - divisibility and primes

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SUMMARY

The discussion centers on proving that any integer n ≥ 2, which divides (n-1)! + 1, is a prime number. Participants emphasize the importance of understanding the implications of divisibility in relation to factorials. The key insight is that if n divides (n-1)! + 1, then none of the integers less than n can divide n, reinforcing the primality of n. This conclusion is critical for those studying number theory and its applications in mathematics.

PREREQUISITES
  • Understanding of factorial notation and properties
  • Basic knowledge of prime numbers and their definitions
  • Familiarity with divisibility rules in number theory
  • Experience with mathematical proofs and logical reasoning
NEXT STEPS
  • Study the properties of prime numbers in number theory
  • Learn about Wilson's Theorem and its applications
  • Explore advanced topics in combinatorial number theory
  • Investigate the implications of divisibility in modular arithmetic
USEFUL FOR

Mathematics students, educators, and enthusiasts interested in number theory, particularly those focused on prime numbers and divisibility concepts.

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Homework Statement


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


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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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