freeCodeCamp/curriculum/challenges/english/08-coding-interview-prep/project-euler/problem-231-the-prime-factorisation-of-binomial-coefficients.english.md

---
id: 5900f4531000cf542c50ff66
challengeType: 5
title: 'Problem 231: The prime factorisation of binomial coefficients'
forumTopicId: 301875
---

## Description
<section id='description'>
The binomial coefficient 10C3 = 120.
120 = 23 × 3 × 5 = 2 × 2 × 2 × 3 × 5, and 2 + 2 + 2 + 3 + 5 = 14.
So the sum of the terms in the prime factorisation of 10C3 is 14.

Find the sum of the terms in the prime factorisation of 20000000C15000000.
</section>

## Instructions
<section id='instructions'>

</section>

## Tests
<section id='tests'>

```yml
tests:
  - text: <code>euler231()</code> should return 7526965179680.
    testString: assert.strictEqual(euler231(), 7526965179680);

```

</section>

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

<div id='js-seed'>

```js
function euler231() {
  // Good luck!
  return true;
}

euler231();
```

</div>



</section>

## Solution
<section id='solution'>

```js
// solution required
```

</section>