---
id: 5900f4041000cf542c50ff17
challengeType: 5
title: 'Problem 152: Writing one half as a sum of inverse squares'
---

## Description
<section id='description'>
There are several ways to write the number 1/2 as a sum of inverse squares using distinct integers.
For instance, the numbers {2,3,4,5,7,12,15,20,28,35} can be used:

In fact, only using integers between 2 and 45 inclusive, there are exactly three ways to do it, the remaining two being: {2,3,4,6,7,9,10,20,28,35,36,45} and {2,3,4,6,7,9,12,15,28,30,35,36,45}.
How many ways are there to write the number 1/2 as a sum of inverse squares using distinct integers between 2 and 80 inclusive?
</section>

## Instructions
<section id='instructions'>

</section>

## Tests
<section id='tests'>

```yml
tests:
  - text: <code>euler152()</code> should return 301.
    testString: assert.strictEqual(euler152(), 301);

```

</section>

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

<div id='js-seed'>

```js
function euler152() {
  // Good luck!
  return true;
}

euler152();
```

</div>



</section>

## Solution
<section id='solution'>

```js
// solution required
```

</section>