AN excellent way to see one’s own country, or one’s own century, is to visit another. While I was making just such a mental pilgrimage to the eighth century, a recent interest in unconventional ...

The p-adics form an infinite collection of number systems based on prime numbers. They’re at the heart of modern number theory. The rational numbers are the most familiar numbers: 1, -5, ½, and every ...

Between each pair of terms in this sequence is the amount the sequence is decreasing by. The 𝒏th term refers to a term's position in the sequence, for example, the first term has 𝒏 = 1, the second ...