exercism/go/perfect-numbers

Perfect Numbers

The Greek mathematician Nicomachus devised a classification scheme for natural numbers.

The Greek mathematican Nicomachus devised a classification scheme for natural numbers, identifying each as belonging uniquely to the categories of abundant, perfect, or deficient. A perfect number equals the sum of its positive divisors — the pairs of numbers whose product yields the target number, excluding the number itself.

• Perfect: Sum of factors = number
• Abundant: Sum of factors > number
• Deficient: Sum of factors < number

The Aliquot sum is defined as the sum of the factors of a number not including the number itself.

Examples

• 6 is a perfect number because its divisors are 1, 2, 3 and 6 = 1 + 2 + 3.
• 28 is perfect number because 28 = 1 + 2 + 4 + 7 + 14.
• Prime numbers 7, 13, etc are Deficient by the Nicomachus classification.

To run the tests simply run the command go test in the exercise directory.

If the test suite contains benchmarks, you can run these with the -bench flag:

go test -bench .

For more detailed info about the Go track see the help page.

Source

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

Submitting Incomplete Problems

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