The Collatz Conjecture is a mathematical problem which states that given any number, and following a simple formula, converges to 1.

Take any number and do this:

  • If odd, multiply by 3 and add 1
  • If even, divide by 2
Repeat. You'll get to 1. Every time.

A comment about the latest xkcd comic's reference to the Collatz Conjecture, which I had never heard of before, lead me to create Hailstone sequence; my first Google AppEngine web app.