Imagine that someone gives you a list of five numbers: 1, 6, 21, 107 and — wait for it — 47,176,870. Can you guess what comes next? If you’re stumped, you’re not alone. These are the first five busy ...

Once upon a time, over 40 years ago, a horde of computer scientists descended on the West German city of Dortmund. They were competing to catch an elusive quarry — only four of its kind had ever been ...