#collatz-1

For any natural number you can apply following procedure: if the number is even divide it by 2 and if the number is odd multiply it by 3 and add 1. The Collatz conjecture states that if we start to repeat that process then ultimately we obtain 1 as a result for every starting number.

https://en.wikipedia.org/wiki/Collatz_conjecture http://mathworld.wolfram.com/CollatzProblem.html http://www.ams.org/bookstore/pspdf/mbk-78-prev.pdf - "The 3x + 1 Problem: An Overview" article