--- id: 5900f3f51000cf542c50ff07 challengeType: 5 title: 'Problem 136: Singleton difference' videoUrl: '' localeTitle: '' --- ## Description undefined ## Instructions undefined ## Tests
```yml tests: - text: '' testString: 'assert.strictEqual(euler136(), 2544559, "euler136() should return 2544559.");' ```
## Challenge Seed
```js function euler136() { // Good luck! return true; } euler136(); ```
## Solution
```js // solution required ```