Moscow. August 17th. INTERFAX.RU – In Japan, the publisher and popularizer of puzzles with Sudoku numbers Maki Kaji has died, the Guardian writes, citing a statement from the Japanese publishing house Nikoli. He was 69 years old, he died on August 10 at home from cancer.
Kaji refined an existing digital puzzle in the mid-1980s when he started working at Nikoli. He published them regularly, discussed them with readers, and eventually began publishing a Sudoku magazine once a quarter. He retired from business only in July 2021 due to illness.
Outside of Japan, Sudoku became popular about two decades ago, when other newspapers began to print them. It is estimated that around 100 million people in the world regularly practice these crosswords, which is believed to help train the brain, preserve memory and the ability to concentrate. Since 2006, annual Sudoku championships have been held.
It is believed that Sudoku is based on a puzzle invented by the Swiss mathematician of the 18th century Leonid Euler, and Kaji is primarily responsible for its popularization and invention of the name – an abbreviation of the Japanese phrase “each number occurs only once.”
