In combinatorics and in experimental design, a Latin square is an n × n array filled with n different symbols, each occurring exactly once in each row and exactly once in each column. An example of a 3×3 Latin square is
Displaying a 7 × 7 Latin square, this stained-glass window at Gonville and Caius College, Cambridge honored Ronald Fisher, whose Design of Experiments discussed Latin squares. The Sir Ronald Fisher window was removed in 2020 because of Fisher's connection with eugenics.
Choi Seok-jeong was a Korean politician and mathematician in the Joseon period of Korea.
Choi Seok-jeong
Gusuryak by Choi Seok-jeong, published in 1700