Hidden Quad
A Hidden Quad is a Hidden Subset of size 4.
When all candidates for 4 digits in a house are limited to only 4 cells, these cells must contain these 4 digits. Subsequently, all remaining candidates can be removed from these 4 cells.
Example
The following example shows a Hidden Quad in the 6th box.
Sudoku Games
Free Sudoku Script for Your Website
Sudoku strategies
- Coloring
- Singles
- Fish
- Chains and Loops
- Intersections
- Subsets
- Wings
- Single Digit Patterns
- Uniqueness
- Almost Locked Sets
Printable Sudoku
- Kids Sudoku Puzzles
- Easy Sudoku Puzzles
- Standard Sudoko Puzzles
- Hard Sudoku Puzzles
- Expert Soduko Puzzles
- Extreme Soduku Puzzles
- Blank Sudoku Grids