For those unfamiliar:

In Cartesian coordinates, if p = (p1, p2,..., pn) and q = (q1, q2,..., qn) are two points in Euclidean n-space, then the distance from p to q, or from q to p is given by:

So I decided to be that reference I was looking for earlier. Here is the implementation in Clojure:

```
(defn square [x]
(* x x))
(defn euclidean-distance [p q]
(Math/sqrt (->> (map - q p) (map square) (reduce +))))
(/ 1 (+ 1 (euclidean-distance [0 4 3 2 0] [5 8 2 1 1])))
# => 0.13100580420257674
```

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