# Sudoku

### What is Sudoku and how to play?

The games objective is to fill the puzzle with numbers ranging from 1 to 9 so that a number will not appear more than one time in any row, column, or region (a region is a 3x3 box, and it is marked with a thicker line). Each Sudoku puzzle contains 9 rows, 9 columns, and 9 regions. How to play Sudoku?

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### How many rows are there in a Sudoku puzzle?

Each Sudoku puzzle contains 9 rows, 9 columns, and 9 regions. How to play Sudoku? When you start to solve a Sudoku puzzle, a part of it is already filled with numbers.

### How do you highlight numbers in Sudoku?

To highlight numbers, click a number that has aready been placed inside the sudoku puzzle. As the game progesses, you may want to use notes. Click the pencil in the right bottom corner to turn the numbers into notes. Just click it again to return to puzzle number form.

### How many types of Sudoku puzzles are there?

The puzzle can be generated by taking a 9×9 grid and dividing it into 9 3×3 boxes. Any number from 1 to 9 can be placed within each of these boxes. Therefore, there are (9!)/ (3!*6!) or 362,880 different Sudoku puzzles that can be created.

### How many rows and columns are in a Sudoku?

One example is a Sudoku with 22 clues (second image). The largest total number of empty groups (rows, columns, and boxes) in a Sudoku is believed to be nine. One example is a Sudoku with 3 empty rows, 3 empty columns, and 3 empty boxes (third image).

### What is the objective of a Sudoku puzzle?

In classic sudoku, the objective is to fill a 9 × 9 grid with digits so that each column, each row, and each of the nine 3 × 3 subgrids that compose the grid (also called boxes, blocks, or regions) contain all of the digits from 1 to 9. The puzzle setter provides a partially completed grid, which for a well-posed puzzle has a single solution.

### How many grids are in a Sudoku board game?

Mathematics of Sudoku. The number of classic 9×9 Sudoku solution grids is 6,670,903,752,021,072,936,960 (sequence A107739 in the OEIS ), or around 6.67×1021. This is roughly 1.2×10−6 times the number of 9×9 Latin squares. Various other grid sizes have also been enumerated—see the main article for details.

### How to Play Sudoku? Sudoku Rule № 1: Use Numbers 1-9; Sudoku is played on a grid of 9 x 9 spaces. Within the rows and columns are 9 “squares” (made up of 3 x 3 spaces). Each row, column and square (9 spaces each) needs to be filled out with the numbers 1-9, without repeating any numbers within the row, column or square.

How many numbers are there in a Sudoku puzzle?