### arrayLcm

Calculates the lowest common multiple (lcm) of an array of numbers.

Use `Array.reduce()` and the `lcm` formula (uses recursion) to calculate the lowest common multiple of an array of numbers.

```js
const arrayLcm = arr => {
  const gcd = (x, y) => !y ? x : gcd(y, x % y);
  const lcm = (x, y) => (x * y) / gcd(x, y);
  return arr.reduce((a, b) => lcm(a, b));
};
```

```js
arrayLcm([1,2,3,4,5]) // 60
arrayLcm([4,8,12]) // 24
```