Collatz Conjucture is a cool and unsolved conjucture/problem named after the German mathematician, Lothar Collatz. It simply asks you pick up any integer n (n>=0). If it’s an even number, halve it, if it’s odd, multiply by 3 and add 1. Apply the same procedure to the resulting number. Conjecture claims that all numbers converge to 1 during this process.
For example, if you start with 7, you get the result of 7, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1, 4, 2, 1, …. All results end up with the 4, 2, 1 loop. All the integers between 1 and 20·2^58 has been tested (with a very simple code piece) so far, and they all end up with the same result. Crazy mathematicians all around the world are still struggling to find a number violating this rule, and come to a theory or pattern, I guess.
