A puzzle enthusiast and publisher, Maki Kaji who was known as “Godfather of Sudoku” died at 69 by duct cancer.
Kaji was a university dropout who worked in a printing company before finding Japan’s first puzzle magazine, with the help of an existing number puzzle, he later named the logic puzzle “Sudoku”.
His company Nikoli said on its website that Kaji was adored by puzzle lovers around the world and we would like to express our gratitude to all of you.
Kaji continued to create and refine puzzles with the help of readers of his quarterly puzzle magazine. He stepped down as head of his company in July because of ill health and died on August 10.
The puzzle challenges people to fill a grid of 9×9 blocks, with nine boxes in each block so that all the boxes contain numbers 1 to 9 without repetitioin. The number of filled figures for a grid at the start of the puzzle determines its difficulty level.