---
id: 5900f3f31000cf542c50ff06
challengeType: 5
title: 'Problem 135: Same differences'
---
## Description
Given the positive integers, x, y, and z, are consecutive terms of an arithmetic progression, the least value of the positive integer, n, for which the equation, x2 − y2 − z2 = n, has exactly two solutions is n = 27:
342 − 272 − 202 = 122 − 92 − 62 = 27
It turns out that n = 1155 is the least value which has exactly ten solutions.
How many values of n less than one million have exactly ten distinct solutions?
## Instructions
## Tests
```yml
tests:
- text: euler135() should return 4989.
testString: assert.strictEqual(euler135(), 4989, 'euler135() should return 4989.');
```
## Challenge Seed
```js
function euler135() {
// Good luck!
return true;
}
euler135();
```