Proving: 6 Divides (n^3-n) for All Integers n

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Homework Statement



prove:6 divides (n^3-n) for all integers n.

Homework Equations


n^3-n=(n)(n+1)(n-1)


The Attempt at a Solution


tried to use direct proof. Then used cases that involed n=2k for some integer k and n=2k+1 for some integer k. However, i could not get it so that 6 was factored from either odd/even of n^3-n i.e. n^3-n=6m for some integer m.
Just a hint please.
 
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What's the remainder on division by 3 of the 3 factors you have exhibited?
 
One of any two consecutive number is even. One of any three consecutive numbers is a multiple of 3.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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