# Questions tagged [sudoku]

The sudoku tag has no usage guidance.

9
questions

**3**

votes

**1**answer

2k views

### Number of solutions and minimal clues in Sixy Sudoku

Sixy Sudoku is a variation on Latin squares and traditional sudoku played on a $6 \times 6$ grid with an initial clue of several cells filled in with a subset of the digits $1$–$6$. The task is to ...

**1**

vote

**0**answers

167 views

### Minimal-information description of sudoku solution (Latin square)

Sudoku puzzles consist of a $9 \times 9$ grid of cells in which some cells contain integers from the set $\{ 1, \ldots, 9 \}$ and the task is to fill in the remaining cells such that the numbers $1$ ...

**1**

vote

**2**answers

233 views

### How to describe the common boundaries between regions in a infinite Sudoku?

This relates to the answer to a question "Who wins two player sudoku?" and this awesome blog.
A Sudoku can be $N \times N$ where $\sqrt{N}$ is a natural number because $N \times N / \sqrt{N} \times \...

**10**

votes

**3**answers

856 views

### The Sudoku game: Solver-Spoiler variation

Consider the Sudoku Solver-Spoiler game, a natural variation of the Sudoku game recently appearing in the question Who wins two-player Sudoku? posted by user PyRulez. In that game, the players attempt ...

**34**

votes

**2**answers

3k views

### Who wins two player sudoku?

Let's say players take turns placing numbers 1-9 on a sudoku board. They must not create an invalid position (meaning that you can not have the same number in within a row, column, or box region). The ...

**3**

votes

**1**answer

160 views

### Algorithms for Fixing Sudokus

Suppose someone got stuck solving a Sudoku and asks you to figure out, what went wrong. Unfortunately that person only sends you a copy of the instance, where you neither see which of the numbers ...

**15**

votes

**1**answer

1k views

### Is there a Sudoku matroid?

This question is inspired from this one, where it is asked what is the minimum number of checks needed to verify that a Sudoku solution is correct. Let
$$
E=\{r_1, \dots, r_9\} \cup \{c_1, \dots, ...

**43**

votes

**4**answers

7k views

### Verifying the correctness of a Sudoku solution

A Sudoku is solved correctly, if all columns, all rows and all 9 subsquares are filled with the numbers 1 to 9 without repetition. Hence, in order to verify if a (correct) solution is correct, one has ...

**14**

votes

**1**answer

2k views

### Gröbner basis for Sudoku

I'm trying to write a program that solves Sudokus using Gröbner bases. I introduced $81$ variables, $x_1$ to $x_{81}$, this is a linearisation of the Sudoku board.
The space of valid Sudokus is ...