Proofs
Both of the proofs (for prime moduli) make use of the fact that the residue classes modulo a prime number are a field. See the article prime field for more details. Lagrange's theorem (in any field a polynomial of degree n has at most n roots) is needed for both proofs.
Read more about this topic: Wilson's Theorem
Famous quotes containing the word proofs:
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—William Shakespeare (1564–1616)
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—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)
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—David Hume (1711–1776)