Inspired by the 18th Century Latin Square

Dubbed as ‘the Rubik’s Cube of the 21st Century’, the puzzle was designed by Howard Garns, a retired architect and was first published by Dell magazines in 1979 under the name of Number Place. It appeared in the American magazine Dell Pencils, Puzzles and Word Games under this name Garns was undoubtedly inspired by the 18th Century Latin Square invention of Swiss mathematician, Leonhard Euler.

Suuji wa dokushin ni kagiru

In 1984 the same puzzle was published in Japan by the Nikoli publishing group under the name of Suuji wa dokushin ni kagiru (which translates as ‘the numbers must be single’ or ‘the numbers must appear only once’) in the Monthly Nikolist. It was later abbreviated to Su Doku. In 1986 the number of givens was restricted to no more than 32 and the puzzles were made ’symmetrical’ by Nikoli, with the givens being distributed in rotationally symmetric cells. The publishing company still holds the trademark of the name Su Doku in Japan and the puzzle is published under many different names in a variety of periodicals.