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su doku

(so͞odō`ko͞o) [Jap.,=single number], a number puzzle consisting, in its classic form, of a square divided into nine squares, with each smaller square divided into nine boxes, thus forming an overall grid of 81 boxes. To solve the puzzle, a single number (from 1 to 9) must be entered in each blank box so that each number is used only once in each smaller square and only once in each row and column in the larger square. A number of the boxes are always filled in by the maker of the puzzle, providing both clues and limitations to where the solver may place numbers, and the degree of difficulty of the puzzle is determined by which numbers the puzzle maker chooses to reveal as clues. Variations include the use of larger or smaller squares than the 9-box-by-9-box classic grid, irregular divisions of the overall grid, and additional restrictions on the placement of the numbers.

The modern origins of sudoku appear to lie with Dell Puzzle Magazines, which has published nine-square "Number Place" puzzles since the 1970s. Such puzzles are based on, but more complicated than, the Latin squares described by the 18th-century Swiss mathematician EulerEuler, Leonhard
, 1707–83, Swiss mathematician. Born and educated at Basel, where he knew the Bernoullis, he went to St. Petersburg (1727) at the invitation of Catherine I, becoming professor of mathematics there on the departure of Daniel Bernoulli (1733).
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. In 1984 Nikoli publishers began publishing sudoku puzzles in Japan. Nikoli limited the number of boxes filled in as clues to less than 30, and required that the clues form a symmetrical pattern. In this form sudoku became popular in Japan and by 2005 common in the United States and other countries.

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Sudoku Snaps - Jewels is now available on the App store and iTunes.
Everybody seems to be able to sudoku better than me.
This is the reason that the accompanying explanation of the rules of Sudoku in many newspapers claims that solving Sudoku requires no mathematics.
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com for enthusiasts of sudoku puzzles; and an online cookbook store can be found at http://www.
uk, with Stumped by Sudoku in the subject line, by December 14.
The Sudoku puzzle board comprises a nine-by-nine grid subdivided into nine smaller grids of three-by-three boxes.
Sudoku fans have three hefty puzzle collections on the latest craze to provide fans with excellent brand new puzzles with varying degrees of difficulty.
Video games company Atomic Planet Enter- tainment has linked up with television presenter Carol Vorderman to make the numbers add up on her bid to spread the word about sudoku.
On our new-look TV, Puzzles and Stars page today we launch our Sudoku challenge.