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Strategies for Number Puzzles of all kinds
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Latest Changes and Additions

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

Related Sets Algorithm
Date Created: Saturday 23-Jul-2016
Last Updated: Saturday 23-Jul-2016
James Pike introduces Related Sets Algorithm

What's New
Date Created: Monday 17-Aug-2009
Last Updated: Friday 15-Jul-2016

Date Created: Friday 11-Apr-2008
Last Updated: Sunday 1-May-2016
Sudoku Strategy. Bugs 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.

Almost Locked Sets
Date Created: Saturday 12-Apr-2008
Last Updated: Sunday 24-Apr-2016
Sudoku Strategy. Almost Locked Sets are complex building blocks that all allow one to continue a chain. They are groups of cells of size N with N+1 candidates in them.

AIC with ALSs
Date Created: Saturday 12-Apr-2008
Last Updated: Saturday 23-Apr-2016

Sudoku Solver - Version History
Date Created: Sunday 13-Apr-2008
Last Updated: Saturday 26-Mar-2016

Windoku Strategy
Date Created: Saturday 26-Mar-2016
Last Updated: Saturday 26-Mar-2016

Unique Rectangles
Date Created: Friday 11-Apr-2008
Last Updated: Sunday 6-Dec-2015
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.

3D Medusa
Date Created: Saturday 6-Mar-2010
Last Updated: Tuesday 6-Oct-2015
Sudoku Strategy. 3D Medusa takes chain building into all the dimensions of the Sudoku board. That is, by making links among rows, columns and boxes - and in bi-value cells. Many types of eliminations are possible with this network approach.

Sword-Fish Strategy
Date Created: Friday 11-Apr-2008
Last Updated: Saturday 1-Aug-2015
Sudoku Strategy. Sword-Fish extends X-Wings into three rows and three columns. Candidate eliminations are possible where the cells that form the Sword-Fish are the only possible places for a solution on candidate N.