The Birthday of Srinivasa Ramanujan (1887) – Again?

Ramanujan’s birth is usually Dec 22 (Tamil calendar). We celebrated him earlier, but one more gem: Ramanujan’s taxicab number (1729) is the smallest number expressible as sum of two cubes in two ways. He also discovered the formula for π: 1/π = (2√2/9801) Σ (4k)!(1103+26390k)/(k!⁴ 396⁴ᵏ). Each term gives roughly 8 decimal places. His mock theta functions were only understood decades later, playing a role in string theory. Ramanujan’s birthday is a day to marvel at how one mind can touch the infinite.