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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:

SK Loops
Date Created: Friday 29-Nov-2019
Last Updated: Friday 29-Nov-2019
SK Loops are eight 2-cell bi-directional continuous loops

Brute Force vs Logical Strategies
Date Created: Wednesday 27-Nov-2019
Last Updated: Wednesday 27-Nov-2019

Remote Pairs
Date Created: Friday 11-Apr-2008
Last Updated: Sunday 17-Nov-2019
Sudoku Strategy. Remote Pairs are a special instance of XY-Chains and was the first type of extended pair-wise chain to be identified. It is isolated for nostalgic reasons.

Gurths Theorem
Date Created: Saturday 28-Sep-2019
Last Updated: Sunday 17-Nov-2019
Gurth's Symmetrical Placement Theory is discussed

Date Created: Friday 11-Apr-2008
Last Updated: Wednesday 20-Feb-2019
Sudoku Strategy. BUG stands for Bi-Value Universal Grave. It is a formation that relies on the uniqueness of the solution and an array of bi-value cells.

Strategy Families
Date Created: Saturday 12-Apr-2008
Last Updated: Wednesday 23-Jan-2019
This is the index to the all the fully documented strategies used to solve Sudoku, Jigsaw Sudoku, Sudoku X and Killer Sudoku.

Using Unique Rectangles as Links in Chains
Date Created: Wednesday 23-Jan-2019
Last Updated: Wednesday 23-Jan-2019

Jellyfish Strategy
Date Created: Friday 11-Apr-2008
Last Updated: Monday 31-Dec-2018
Sudoku Strategy. Jelly-Fish extends Sword-Fish into four rows and four columns. Candidate eliminations are possible where the cells that form the Jelly-Fish are the only possible places for a solution on candidate N."

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