--- id: 5900f43a1000cf542c50ff4d challengeType: 5 title: 'Problem 206: Concealed Square' forumTopicId: 301847 --- ## Description
Find the unique positive integer whose square has the form 1_2_3_4_5_6_7_8_9_0, where each “_” is a single digit.
## Instructions
## Tests
```yml tests: - text: euler206() should return 1389019170. testString: assert.strictEqual(euler206(), 1389019170); ```
## Challenge Seed
```js function euler206() { return true; } euler206(); ```
## Solution
```js // solution required ```