For the fourth time in the history of the annual William Lowell Putnam Mathematical Competition, and for the fourth year in a row, all five of the top spots in the contest, known as Putnam Fellows, came from a single school: MIT. Putnam Fellows include three individuals who ranked in the top five in previous years — sophomores Papon Lapate and Luke Robitaille and junior Brian Liu — plus junior Ankit Bisain and first-year Jiangqi Dai. Each receives an award of $2,500. MIT’s 2023 Putnam Team, made up of Bisain,…