I just have one question about the proof. Why does [itex](p-1)!a^{p-1}=(p-1)!\pmod{p}[/itex]? It seems like it would be true if the (mod p) was instead (mod a).(adsbygoogle = window.adsbygoogle || []).push({});

Thanks for your help.

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# Proof of Fermat's Little Theorem

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