EditorialPo-Shen Loh, two-time winning coach of the USA Math Olympiad Team, gives a talk on mathematical puzzles at the Museum of Math in New York on Aug. 23, 2016. (Christian Hansen/The New York Times)
EditorialPo-Shen Loh, two-time winning coach of the USA Math Olympiad Team, gives a talk on mathematical puzzles at the Museum of Math in New York on Aug. 23, 2016. (Christian Hansen/The New York Times)