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# fermt litle theorem Tweet

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1. fermt litle theorem
Let p be a prime. Prove that if a is an element of Z*_p then a^(p-1) = 1, i.e. for any integer a not divisible by p, a^p-1 is equivalent to 1 (mod p)

find 2^183 (mod37)
Let p be a prime. Prove that if a is an element of Z*_p then a^(p-1) = 1, i.e. for any integer a not divisible by p, a^p-1 is equivalent to 1 (mod p)

find 2^183 (mod37)
From FLT 2^36 = 1 mod 37.

So 2^183 = 2^180 * 2^3 = (2^36)^5 * 2^3 = 1^5 * 2^3 = 8 (mod 37)
3. The proof is available on many websites. Just do a quick google search.

2^36 = 1 (mod 37) and 36*5=180, then:
2^183 = 2^(180) . 2^3 = 2^(36)^5 . 2^3 = 1^5 . 2^3 = 8 (mod 37)
4. I have to start posting faster...