This week’s challenge was suggested by Jordan Ellenberg, a math-world superstar and current professor of mathematics at the University of Wisconsin. Jordan is the child prodigy who turned out well. After teaching himself to read at age 2, he attained a perfect 800 on the math portion of the SAT at age 12, won two gold medals in the International Math Olympiad (with perfect scores), and was a two-time Putnam Fellow at Harvard.