freeCodeCamp/curriculum/challenges/chinese/10-coding-interview-prep/project-euler/problem-454-diophantine-reciprocals-iii.md

---
id: 5900f5331000cf542c510045
challengeType: 5
videoUrl: ''
title: 问题454：丢番图倒数III
---

## Description
<section id="description">在下面的等式中，x，y和n是正整数。 <p> 1x + 1y = 1n </p><p>对于极限L，我们将F（L）定义为满足x &lt;y≤L的解的数量。 </p><p>我们可以验证F（15）= 4和F（1000）= 1069.找到F（1012）。 </p></section>

## Instructions
<section id="instructions">
</section>

## Tests
<section id='tests'>

```yml
tests:
  - text: <code>euler454()</code>应该返回5435004633092。
    testString: assert.strictEqual(euler454(), 5435004633092);

```

</section>

## Challenge Seed
<section id='challengeSeed'>

<div id='js-seed'>

```js
function euler454() {
  // Good luck!
  return true;
}

euler454();

```

</div>



</section>

## Solution
<section id='solution'>

```js
// solution required
```

/section>