A shower thought turned into a Collatz visualization
Published on: 2025-07-02 09:04:14
A shower thought turned into a beautiful Collatz visualization
I recently went on a nice long SCUBA diving trip with my wife and daughters. Lots of diving implies lots of showers, and lots of showers means lots of shower-thoughts! An especially interesting one I had turned into a nice way to visualize some aspects of the Collatz Conjecture.
The Collatz Conjecture defines a very simple function on all positive integers as follows:
If the number is even, divide it by 2
If the number is odd, multiply it by 3 and then add 1
If you can prove that repeated applications of this function, starting from any positive integer, will eventually reach 1 then you have proved the Collatz Conjecture and won a million dollars and plenty of fame and glory!
Individual inputs are trivial to verify. For example, if we start with 6, we get:
6 is even, so 6 / 2 → 3
3 is odd, so 3 × 3 + 1 → 10
10 is even, so 10 / 2 → 5
5 is odd, so 5 × 3 + 1 → 16
16 is even, so 16 / 2 → 8
8 is even, so 8 / 2 → 4
4
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