Thanks to the wonderful mathematic explanation of Matt Parker in the video where he explained that the number 4 is the only number that has the same number of letters as its value in some languages, such as DE, NL and EN.
"4 is is a fixed point, it doesn't go anywhere. It maps to itself."
- Matt Parker
Matt explained that no matter what number you would take, it would always end up at the number 4. So I wrote a script that uses his logic from the video in a function that shows the output of the sequence to test wether it is true or not.
NOTE: Only [a-zA-Z] are taken into account when counting the characters. Any
other character is ignored.
Example run:
$ ./four.py 847193 en
==============================
STARTING SEQUENCE
starting number => 847.193
==============================
847.193 => eight hundred and forty-seven thousand, one hundred and ninety-three => 57
57 => fifty-seven => 10
10 => ten => 3
3 => three => 5
5 => five => 4
==============================
$ git clone https://github.com/kkoomen/4-four.git
$ cd 4-four
$ pip3 install virtualenv
$ virtualenv .
$ source bin/activate
$ pip3 install -r requirements.txt