Choe Seok-jeong's order-nine Latin squares
Cuadrados latinos de orden nueve de Choe Seok-jeong
- Date
- 1700 · confidence high
- Place
- Hanseong (Seoul), Joseon, Korea (present-day South Korea)
- Credited to
- Choe Seok-jeong
- Field
- Knowledge & symbols
What was discovered
Korean mathematician and statesman Choe Seok-jeong published the earliest known example of order-nine Latin squares, used to construct a magic square, 67 years before Euler studied the problem systematically in Europe.
The coordinate is set at the Korean capital (Hanseong, today Seoul) with low geographic confidence, as the exact place where Choe did the work is not recorded; his career unfolded at the Joseon court.
What it led to
- General theory of Latin squares (Euler, 1782)
- Statistical experimental design (Fisher's Latin squares, 20th century)
- Modern combinatorics