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5:42 AM
You can use the following:
$$a^x \equiv 1 \pmod{p}$$
where $x = p^{n-1}(p-1)$
 
 
8 hours later…
1:42 PM
@Haran did you mean $a^x \equiv 1 \pmod {p^n}$?
 
2:34 PM
Yes, sorry
 
2:50 PM
Alright thank you @Haran
 

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