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# Prime Factors

Compute the prime factors of a given natural number.

A prime number is only evenly divisible by itself and 1.

Note that 1 is not a prime number.

## Example

What are the prime factors of 60?

- Our first divisor is 2. 2 goes into 60, leaving 30.
- 2 goes into 30, leaving 15.
  - 2 doesn't go cleanly into 15. So let's move on to our next divisor, 3.
- 3 goes cleanly into 15, leaving 5.
  - 3 does not go cleanly into 5. The next possible factor is 4.
  - 4 does not go cleanly into 5. The next possible factor is 5.
- 5 does go cleanly into 5.
- We're left only with 1, so now, we're done.

Our successful divisors in that computation represent the list of prime
factors of 60: 2, 2, 3, and 5.

You can check this yourself:

- 2 * 2 * 3 * 5
- = 4 * 15
- = 60
- Success!

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](http://exercism.io/languages/go).

## Source

The Prime Factors Kata by Uncle Bob [http://butunclebob.com/ArticleS.UncleBob.ThePrimeFactorsKata](http://butunclebob.com/ArticleS.UncleBob.ThePrimeFactorsKata)

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