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Latest Changes and Additions

A quick list of the latest updates and additions to this site:

Interesting Sudokus
Date Created: Tuesday 4-Sep-2018
Last Updated: Tuesday 27-Nov-2018

How Sudoku X Breaks Symmetries
Date Created: Wednesday 7-Aug-2013
Last Updated: Friday 21-Sep-2018

Sudoku Solver for Android
Date Created: Saturday 15-Dec-2012
Last Updated: Sunday 26-Nov-2017

Empty Rectangles
Date Created: Saturday 12-Apr-2008
Last Updated: Sunday 26-Nov-2017
Sudoku Strategy. Empty Rectangles is a complex strategy that uses a variety of formations and the fact that a Sudoku puzzle should have a unique solution.

Grouped X-Cycles
Date Created: Saturday 12-Apr-2008
Last Updated: Friday 24-Nov-2017
Sudoku Strategy. All chains used in Alternating Inference Chains strategies can take advantage of grouped cells for the purpose of finding links. This explains how.

Sudoku Solver - Version History
Date Created: Sunday 13-Apr-2008
Last Updated: Friday 8-Sep-2017

Hidden Candidates
Date Created: Wednesday 9-Apr-2008
Last Updated: Tuesday 24-Jan-2017
Sudoku Strategy. Hidden Pairs, Triples and so on - these are the candidates in cells aligned on a row, column and box which can be used to remove other candidates the formation is aligned with.

Naked Candidates
Date Created: Thursday 9-Jun-2005
Last Updated: Tuesday 24-Jan-2017
Sudoku Strategy. Naked Pairs, Triples and so on - these are the remaining candidates left in cells aligned on a row, column and box which can be used to remove other candidates the formation is aligned with.

Exocet
Date Created: Wednesday 26-Oct-2016
Last Updated: Monday 9-Jan-2017

Double Exocet
Date Created: Sunday 4-Dec-2016
Last Updated: Sunday 4-Dec-2016
Sudoku Strategy: Very powerful elimination sets can be deduced from the overlap of two Exocet patterns