Luoshu Square
The Luoshu (pinyin), Lo Shu (Wade-Giles), or Nine Halls Diagram is an ancient Chinese diagram and named for the Luo River near Luoyang, Henan. The Luoshu appears in myths concerning the invention of writing by Cangjie and other culture heroes. It is a unique normal magic square of order three. It is usually paired with the River Map or Hetu—named in reference to the Yellow River—and used with the River Map in various contexts involving Chinese geomancy, numerology, philosophy, and early natural science.
The Secret of Luo Shu: Numerology in Chinese Art and Architecture by Lars Berglund