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---
id: 5900f4d61000cf542c50ffe9
title: 'Problem 362: Squarefree factors'
challengeType: 5
forumTopicId: 302023
dashedName: problem-362-squarefree-factors
---
# --description--
Consider the number 54.
54 can be factored in 7 distinct ways into one or more factors larger than 1:
$$54, 2 × 27, 3 × 18, 6 × 9, 3 × 3 × 6, 2 × 3 × 9 \text{ and } 2 × 3 × 3 × 3$$
If we require that the factors are all squarefree only two ways remain: $3 × 3 × 6$ and $2 × 3 × 3 × 3$.
Let's call $Fsf(n)$ the number of ways $n$ can be factored into one or more squarefree factors larger than 1, so $Fsf(54) = 2$.
Let $S(n)$ be $\sum Fsf(k)$ for $k = 2$ to $n$.
$S(100) = 193$.
Find $S(10\\,000\\,000\\,000)$.
# --hints--
`squarefreeFactors()` should return `457895958010`.
```js
assert.strictEqual(squarefreeFactors(), 457895958010);
```
# --seed--
## --seed-contents--
```js
function squarefreeFactors() {
return true;
}
squarefreeFactors();
```
# --solutions--
```js
// solution required
```