His Japanese publisher announced that the man who was known as the “father of Sudoku” because of his contribution to popularizing the mathematical brainteaser, has died from cancer at the age of 69.

A notice was posted Monday by Nikoli stating that Maki Kaji had died at home on Tuesday, August 10, after fighting cancer. A memorial service will be held at a later time.

The publisher released a statement on its site stating that Mr Kaji was “known as the father of Sudoku” and was beloved by puzzle lovers all over the globe.

Leonhard Euler, a Swiss mathematician, invented Sudoku in the 18th Century.

It is often said that the modern version was formulated in the United States. However, Kaji is credited for popularizing the puzzle.

It is believed that he also invented the name Sudoku. This is a contraction from a Japanese phrase which means “each number must have one”.

Sudoku asks players to place the numbers 1-9 in a box of 81 squares.

The grid can also be sub-divided into nine blocks that each contain nine single squares. Each block must contain the numbers 1 to 9.

Although it is called Latin Squares, its original concept — a grid where every number or symbol appears once in each row — was created by Euler in the 18th Century.

In the 1980s, Nikoli saw a similar version in an American magazine and brought it to Japan. Sudoku was born there.

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It was introduced to Europe and the United States decades later. In 2005, Britain’s BBC wrote about the puzzle that “began its gentle assault on the nation last January and can now be found at four national newspapers”.

Kaji explained to the BBC that creating a new puzzle was similar to “finding treasure” in 2007.

It’s not about making money. It’s purely about the thrill of solving it.”