## July 2017 Fiendish Function

The Fiendish Function posed during July 2017 had the following sample guesses and replies:

- 1
- 8
- 2
- 5
- 3
- 0
- 4
- 83
- 5
- 74
- 10
- 899

The rule was: "Square the number, then convert each digit to 9 minus the digit".

Suppose the guess was 13:

- Square the number, giving 169.
- Convert each digit to 9 minus the digit, giving 830.

So the result is 830.

## Earlier answers

Here are the answers to the Fiendish Functions posted in earlier months: