Experienced mathematicians warn up-and-comers to stay away from the Collatz conjecture. It’s a siren song, they say: Fall under its trance and you may never do meaningful work again. The Collatz ...

Mathematicians regard the Collatz conjecture as a quagmire and warn each other to stay away. But now Terence Tao has made more progress than anyone in decades. Experienced mathematicians warn ...

This column comes with a warning: Do not try to solve this math problem. You will be tempted. This problem is simply stated, easily understood, and all too inviting. Just pick a number, any number: If ...

The Collatz conjecture is an unsolved conjecture in mathematics. It is named after Lothar Collatz, who first proposed it in 1937. The conjecture is also known as the 3n + 1 conjecture, as the Ulam ...

Some years ago, I wrote here about “hailstone numbers” (Follow that hailstone, 8 April 2016). These are numbers that are generated when you try your hand at the Collatz Conjecture—sometimes described ...