elm/exercises/difference-of-squares/README.md

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# Difference Of Squares
Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.
The square of the sum of the first ten natural numbers is
(1 + 2 + ... + 10)² = 55² = 3025.
The sum of the squares of the first ten natural numbers is
1² + 2² + ... + 10² = 385.
Hence the difference between the square of the sum of the first
ten natural numbers and the sum of the squares of the first ten
natural numbers is 3025 - 385 = 2640.
## Elm Installation
Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm
installation and learning resources.
## Writing the Code
The first time you start an exercise, you'll need to ensure you have the
appropriate dependencies installed.
```bash
$ npm install
```
Execute the tests with:
```bash
$ npm test
```
Automatically run tests again when you save changes:
```bash
$ npm run watch
```
As you work your way through the test suite, be sure to remove the `skip <|`
calls from each test until you get them all passing!
## Source
Problem 6 at Project Euler [http://projecteuler.net/problem=6](http://projecteuler.net/problem=6)
## Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.