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# Perfect Numbers

Determine if a number is perfect, abundant, or deficient based on
Nicomachus' (60 - 120 CE) classification scheme for natural numbers.

The Greek mathematician [Nicomachus](https://en.wikipedia.org/wiki/Nicomachus) devised a classification scheme for natural numbers, identifying each as belonging uniquely to the categories of **perfect**, **abundant**, or **deficient** based on their [aliquot sum](https://en.wikipedia.org/wiki/Aliquot_sum). The aliquot sum is defined as the sum of the factors of a number not including the number itself. For example, the aliquot sum of 15 is (1 + 3 + 5) = 9

- **Perfect**: aliquot sum = number
  - 6 is a perfect number because (1 + 2 + 3) = 6
  - 28 is a perfect number because (1 + 2 + 4 + 7 + 14) = 28
- **Abundant**: aliquot sum > number
  - 12 is an abundant number because (1 + 2 + 3 + 4 + 6) = 16
  - 24 is an abundant number because (1 + 2 + 3 + 4 + 6 + 8 + 12) = 36
- **Deficient**: aliquot sum < number
  - 8 is a deficient number because (1 + 2 + 4) = 7
  - Prime numbers are deficient

Implement a way to determine whether a given number is **perfect**. Depending on your language track, you may also need to implement a way to determine whether a given number is **abundant** or **deficient**.

The Scala exercises assume an SBT project scheme. The exercise solution source
should be placed within the exercise directory/src/main/scala. The exercise
unit tests can be found within the exercise directory/src/test/scala.

To run the tests simply run the command `sbt test` in the exercise directory.

For more detailed info about the Scala track see the [help
page](http://exercism.io/languages/scala).


## Source

Taken from Chapter 2 of Functional Thinking by Neal Ford. [http://shop.oreilly.com/product/0636920029687.do](http://shop.oreilly.com/product/0636920029687.do)

## Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.

Version data entries

74 entries across 74 versions & 1 rubygems

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trackler-2.2.1.159 tracks/scala/exercises/perfect-numbers/README.md
trackler-2.2.1.158 tracks/scala/exercises/perfect-numbers/README.md
trackler-2.2.1.157 tracks/scala/exercises/perfect-numbers/README.md
trackler-2.2.1.156 tracks/scala/exercises/perfect-numbers/README.md
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trackler-2.2.1.152 tracks/scala/exercises/perfect-numbers/README.md
trackler-2.2.1.151 tracks/scala/exercises/perfect-numbers/README.md
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trackler-2.2.1.147 tracks/scala/exercises/perfect-numbers/README.md
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trackler-2.2.1.140 tracks/scala/exercises/perfect-numbers/README.md