(Courtesy: All images Andria Rogava) As you might expect, a four-level pyramid has a triangular cross-section, with 10 balls at the bottom, followed by six in the next layer, then three and finally ...

Now, in the latest exciting development, I have built a new, record-breaking tower with 34 balls (n = 11), in which all 30 balls from the second to the eleventh layer are kept in equilibrium ... see ...