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Collatz Sequence
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.. tags:: tiny, beginner, math



The Collatz sequence, also called the 3n + 1 problem, is the simplest
impossible math problem. (But don’t worry, the program itself is easy enough
for beginners.) From a starting number, n, follow three rules to get the next
number in the sequence:

* If n is even, the next number n is n / 2.
* If n is odd, the next number n is n * 3 + 1.
* If n is 1, stop. Otherwise, repeat.

It is generally thought, but so far not mathematically proven, that every
starting number eventually terminates at 1. More information about the Collatz
sequence can be found at https://en.wikipedia.org/wiki/Collatz_conjecture.


.. collapse:: collatz_sequence.py

   .. literalinclude:: collatz_sequence.py
      :language: python
      :linenos:


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