http://www.sudokuguy.com
An advanced technique for players who like to solve difficult puzzles. It takes practice to spot this pattern.
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http://www.sudokuguy.com
An advanced technique for players who like to solve difficult puzzles. It takes practice to spot this pattern.
http:///www.sudokuguy.com
this is a valuable tutorial. spotting a 3X3 and knowing what can happen is so exciting.
http://www.sudokuguy.com
This is another advanced technique which is rare and difficult to spot.https://www.youtube.com/watch?v=kzXjcuiX0UQ&list=PLAhxvOuSHpkZuIIZA58Mwz7ekYCk4wjXl&index=41
http://www.sudokuguy.com
The XYZ wing. This is a pattern which is hard to spot. Have fun spotting it in a puzzle.https://www.youtube.com/watch?v=4h7UvI8HfOw&index=40&list=PLAhxvOuSHpkZuIIZA58Mwz7ekYCk4wjXl
http://www.sudokuguy.com
https://www.youtube.com/watch?v=H6QD6dESJyw&index=39&list=PLAhxvOuSHpkZuIIZA58Mwz7ekYCk4wjXlThis is tutorial #41. It is the second of 2 tutorials where I show the "outside the puzzle" technique. this technique is essential for difficult puzzle where 3 or more empty cells are in a row, column, or block.
http://www.sudokuguy.com. There are many patterns to watch for to solve very difficult puzzles. This is one of several tutorials showing what to look for. It is amazing how recongnizing patterns enable you to solve to the end of the puzzle. There are many ways to eliminate small numbers.
http://www.sudokuguy.com https://www.youtube.com/watch?v=V2FMdHPDT5c&list=PLAhxvOuSHpkZuIIZA58Mwz7ekYCk4wjXl&index=35
This is powerful. The effect of 1 # repeated in a row or column. This can happen in difficult puzzles when you have had to enter all possible numbers in each empty cell