# Getting Started with Checkerboard Sudoku

This tutorial applies to Puzzle Maker Pro - Checkerboard Sudoku.

## Checkerboard Sudoku

Checkerboard is a sudoku variation with a specific grid setup: Like a checkerboard.

To solve a Checkerboard Sudoku, you apply the same rules as for regular sudoku, and additionally you have the Checkerboard rule: The white squares contain only odd numbers, the gray squares contain only even numbers.

This is a fun innovative sudoku variation. Because it's easier to solve - it has less options for each square - it's a great variation to include in activity books for children and adults.

Because Checkerboard Sudoku requires an even number of rows and columns in the grid, this variation is not available with a 9x9 grid.

### Checkerboard Sudoku math

To compare the number of options of Checkerboard Sudoku with regular sudoku, here's the math for the first 3 squares in a 8x8 sudoku grid:

In a regular sudoku, you have 8 options for the first cell, 7 for the next, 6 for the next, and 5 different options for the fourth cell, which would be 8 * 7 * 6 * 5 = 1680 different options for the first 4 cells. (for a full grid, the math becomes increasingly more complex, and the number of options are bilions.

For Checkerboard sudoku, you have 4 options for the first cell: just 1, 3, 5, 7. Then 4 options for the next (2, 4, 6, 8). For the third and fourth cells there are only 3 options. For just the first 4 cells you have 4 * 4 * 3 * 3 = 144 options, which is less than 10% of the regular sudoku options. The difference gets increasingly larger when we add more cells.

## Find Checkerboard Sudoku in Puzzle Maker Pro

To create Checkerboard Sudoku puzzles in Puzzle Maker Pro:

- Go to Sudoku Variations
- Select one of the Sudoku Grid Sizes that are available for Checkerboard Sudoku (6x6, 8x8, 10x10, 12x12, 14x14, 16x16)
- Select "Checkerboard" in the Variation menu.

There are quite a few tutorials about all the regular features of Sudoku in Puzzle Maker Pro, ranging from grid setup to symbol options, please check the tutorials below.

Note: Even though it's possible to use images for Checkerboard Sudokus, it doesn't make much sense, and the sudokus may be impossible to solve, since there are no odd and even images.