Mathematician Terence Tao Cracks a ‘Dangerous’ Problem

But legitimate proofs are rare. In the 1970s, mathematicians showed that almost all Collatz sequences—the list of numbers you get as you repeat the process—eventually reach a number that’s smaller than where you started—weak evidence, but evidence nonetheless, that almost all Collatz sequences incline toward 1. From 1994 until Tao’s result this year, Ivan Korec […]