Consider the following operation: if a number is even, divide by 2. If the number is odd, multiply by 3 and add 1. By repeating this operation, you get the Collatz sequence for your starting number. Does the sequence always eventually hit 1? The Collatz conjecture speculates the answer is yes, but no one knows for sure. Drag the slider for a to whatever starting value you like. Then slide n over to the 1 value, and slowly increase n. This will give you the values of the Collatz sequence, as well as a graph of those values.