Show that one and only one out of `n ,n+2or ,n+4` is divisible by 3, where `n` is any positive integer.

Explanation

Since` n, n+1, n+2 `are three consecutive integers then there must be one number divisible by `3` at least.



If the remainder at dividing` n` by `3` is `1`, then` n+2` must be divisible by` 3` and if the remainder at dividing `n` by `3` is `2`, then `n+1` must be divisible by `3`. Similarly for` n+1 and n+2.`




Let n be divisible by `3`.
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