---
id: 5900f4291000cf542c50ff3a
challengeType: 5
title: 'Problem 187: Semiprimes'
forumTopicId: 301823
---

## Description
<section id='description'>
A composite is a number containing at least two prime factors. For example, 15 = 3 × 5; 9 = 3 × 3; 12 = 2 × 2 × 3.

There are ten composites below thirty containing precisely two, not necessarily distinct, prime factors:
4, 6, 9, 10, 14, 15, 21, 22, 25, 26.

How many composite integers, n < 108, have precisely two, not necessarily distinct, prime factors?
</section>

## Instructions
<section id='instructions'>

</section>

## Tests
<section id='tests'>

```yml
tests:
  - text: <code>euler187()</code> should return 17427258.
    testString: assert.strictEqual(euler187(), 17427258);

```

</section>

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

<div id='js-seed'>

```js
function euler187() {
  // Good luck!
  return true;
}

euler187();
```

</div>



</section>

## Solution
<section id='solution'>

```js
// solution required
```

</section>