where F n are the Fibonacci numbers 0, 1, 1, 2, 3, … and L n are the Lucas numbers 2, 1, 3, 4, 7, …. These are two sequences satisfying the same famous recurrence relation, just with different initial ...

Sep 24, 2026 These seven equations between binomial coefficients are ‘coincidences’: they aren’t among the four known infinite families of such equations. Here we explain one using representation ...

Let’s climb up to the E 6 root polytope starting with some of its 4-dimensional faces, which are called 4-demicubes because you get them by taking a 4-dimensional cube, or tesseract, and removing ...