Can a computer think for itself? We can use computers and other digital devices to do lots of different things. We can send messages, go shopping, watch a video or play a game. Many of the machines ...

The original version of this story appeared in Quanta Magazine. 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 ...