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Sudoku

Sample

Progressing

Solution

Rules

  1. Place a number from 1 to 9 in each empty cell.
  2. Each row, column, and 3×3 block bounded by bold lines (nine blocks) contains all the numbers from 1 to 9.

Features

Sudoku is very simple to learn, requires no calculations, and provides a surprisingly wide variety of logic situations. All that is required to solve Sudoku is brains and concentration. No wonder Sudoku is among the most popular puzzles in Japan.
>>Why hand made?

History

The Sudoku Puzzle is not our original puzzle. We found this puzzle in an American puzzle magazine, where it was titled “Number Place,” and we introduced it to our Japanese readers at 1984. First our title for this puzzle was “Suuji wa dokushin ni kagiru.” Translated it means that the number is limited to only a single (unmarried) one. But this title was too long, and it was abbreviated to “Sudoku”. Here “SU” means number and “DOKU” means single.

Back then, Sudoku did not become popular immediately, and in 1986 we decided on a rule for making this puzzle: that clues must be arranged in a symmetrical pattern. After our improvement, the puzzle became a big hit.

Popularity in Japan

At present there are five publishers with monthly Sudoku magazines, with a total circulation of maybe 660,000. “Sudoku” is a Nikoli registered trademark in Japan, so the other companies call it “Number Place.” Sudoku is the most popular logic puzzle in Japan. It is very simple to learn, requires no calculations, and provides a surprisingly wide variety of logic situations. Everybody, from children to the aged can enjoy and pass the time with it.

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