---
id: 5900f4181000cf542c50ff2b
challengeType: 5
title: 'Problem 172: Investigating numbers with few repeated digits'
---

## Description
<section id='description'>
How many 18-digit numbers n (without leading zeros) are there such that no digit occurs more than three times in n?
</section>

## Instructions
<section id='instructions'>

</section>

## Tests
<section id='tests'>

```yml
tests:
  - text: <code>euler172()</code> should return 227485267000992000.
    testString: assert.strictEqual(euler172(), 227485267000992000, '<code>euler172()</code> should return 227485267000992000.');

```

</section>

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

<div id='js-seed'>

```js
function euler172() {
  // Good luck!
  return true;
}

euler172();
```

</div>



</section>

## Solution
<section id='solution'>

```js
// solution required
```
</section>
