First let's start by expanding \(n^3 - n\):
$$ n(n^2-1) $$$$ n(n+1)(n-1) $$
If you consider any 3 consecutive numbers, one of them would be divisible by 3. This means:
$$3 | (n-1) * n * (n+1)$$
First let's start by expanding \(n^3 - n\):
If you consider any 3 consecutive numbers, one of them would be divisible by 3. This means: