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Strategies for Number Puzzles of all kinds
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A quick list of the latest updates and additions to this site:

Date Created: Wednesday 3-Nov-2021
Last Updated: Wednesday 3-Nov-2021
Glossary of Sudoku Terms

Cage Unit Overlap
Date Created: Tuesday 22-Mar-2011
Last Updated: Friday 23-Jul-2021
Killer Sudoku Strategy. Cage Unit Overlap looks at the intersection of a cage with a row, column or box to find eliminations.

What's New
Date Created: Monday 17-Aug-2009
Last Updated: Tuesday 13-Jul-2021

Date Created: Wednesday 26-Oct-2016
Last Updated: Friday 2-Jul-2021

Double BUG
Date Created: Thursday 20-May-2021
Last Updated: Thursday 20-May-2021
An investigation into the potential of BUG by John Libbey

Unique Rectangles
Date Created: Friday 11-Apr-2008
Last Updated: Saturday 30-Jan-2021
Sudoku Strategy. Unique Rectangles takes advantage of the fact that published Sudokus have only one solution. There are many formations and strategies based on this notion and they are explained here.

Sudoku's Invariant Regions
Date Created: Friday 1-May-2020
Last Updated: Friday 1-May-2020
Where we show that a new symmetry exists between certain regions

AICs with Exotic Links
Date Created: Wednesday 29-Apr-2020
Last Updated: Wednesday 29-Apr-2020
Using more exotic links to make Alternating Inference Chains

Sudoku Solver - Version History
Date Created: Sunday 13-Apr-2008
Last Updated: Wednesday 29-Apr-2020

Sudoku Solver for Android
Date Created: Saturday 15-Dec-2012
Last Updated: Monday 30-Mar-2020