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Would like a proofreading of my proof

Prove that if $n$ is positive integer, then $n^2$ is divisible by $3$ with remainder either $0$ or $1$.

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marked as duplicate by Jyrki Lahtonen, Srivatsan, Quixotic, Rasmus, mixedmath Oct 23 '11 at 16:33

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

a duplicate – Jyrki Lahtonen Oct 23 '11 at 14:53
@evodevo: Don't take it personally that this is being closed. A house rule. I'm sure you will learn enough by studying the answers of the duplicate question. – Jyrki Lahtonen Oct 23 '11 at 18:02

Hint: $$ 0^2=0\mod 3, $$

$$ 1^2=1\mod 3, $$

$$ 2^2=4=1\mod 3. $$

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So basically, your proof would be the above, except you would omit the word "hint" and replace "Use that" with "Since" :) – The Chaz 2.0 Oct 23 '11 at 14:46
(As the answer originally appeared...+1, btw) – The Chaz 2.0 Oct 23 '11 at 17:55
I turned my answer into something that is more like a hint and less like a full answer. – Rasmus Oct 23 '11 at 19:56

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