Sudoku was the training.
Suirodoku is the real game.
What is Suirodoku?
Suirodoku is the first playable Graeco-Latin Sudoku square linking digits and colors. A 9×9 grid where each cell contains a unique digit-color pair. Both digits and colors satisfy Sudoku constraints (row, column, block), and Graeco-Latin orthogonality ensures each of the 81 pairs appears exactly once.
4 Rules, 1 Ultimate Challenge
Suirodoku combines Sudoku constraints with Graeco-Latin square orthogonality:
- Each row contains numbers 1-9 and all 9 colors
- Each column contains numbers 1-9 and all 9 colors
- Each 3×3 region contains numbers 1-9 and all 9 colors
- Each color contains numbers 1-9 (the 4th rule!)
81 Unique Pairs
The Graeco-Latin orthogonality creates a bijection: each of the 81 digit-color pairs appears exactly once. Unlike Sudoku where each number repeats 9 times, every cell in Suirodoku has an absolute identity — the ultimate logic puzzle challenge.
Rainbow Technique
Track each number across all 9 colors to identify the missing color. The number reveals the color.
A revolutionary sudoku solving strategy.
Chromatic Circle
Track each color across all 9 numbers to identify the missing number. The color reveals the number.
An advanced brain training method.
Sudoku vs Suirodoku
Sudoku
- 3 constraints
- Numbers only
- Each number repeated 9 times
- Classic techniques
Suirodoku
- 4 constraints + Graeco-Latin bijection
- Numbers AND colors intertwined
- 81 unique pairs
- Exclusive techniques
Frequently Asked Questions
What is Suirodoku?
Suirodoku is the first playable Graeco-Latin Sudoku square linking digits and colors: a 9×9 grid combining Sudoku constraints with Graeco-Latin square orthogonality. Each cell contains a unique digit-color pair, both projections satisfy Sudoku rules, and each of the 81 pairs appears exactly once.
What are the rules of Suirodoku?
Like Sudoku, each row/column/3×3 region must contain numbers 1-9. Additionally, each row/column/region must contain all 9 colors, and each digit-color pair appears exactly once in the grid — the Graeco-Latin orthogonality constraint.
Is Suirodoku free to play?
Yes. You can play Suirodoku for free online in your browser.
What are Rainbow and Chromatic Circle techniques?
Rainbow tracks a number across all 9 colors to find the missing color. Chromatic Circle tracks a color across all 9 numbers to find the missing number.