I open this thread to get full list of anticorner maximal invalid patterns.
Invalid patterns have no valid Sudoku puzzles, i.e. no valid Sudoku puzzles can have invalid patterns clue cells' configuration. Maximal invalid pattern is such kind of invalid patterns that becomes valid pattern by adding any one clue cell to the pattern.
Anticorner patterns have such configuration:
- Code: Select all
Anticorner pattern
+-----+-----+-----+
| | | |
| ? | ? | ? |
| | | |
+-----+-----+-----+
| | |x x x|
| ? | ? |x x x|
| | |x x x|
+-----+-----+-----+
| |x x x|x x x|
| ? |x x x|x x x|
| |x x x|x x x|
+-----+-----+-----+
Anticorner pattern has 9 clues in B6, B8 and B9 boxes (or can be morphed to this form).
Here is an example of (valid) anticorner pattern:
- Code: Select all
Anticorner pattern's example
+-----+-----+-----+
|. . x|. . .|. . .|
|. x .|. . .|. . .|
|x . x|. . .|. . .|
+-----+-----+-----+
|. . .|. . .|x x x|
|. . .|. . x|x x x|
|x . .|. . .|x x x|
+-----+-----+-----+
|. . .|x x x|x x x|
|. . .|x x x|x x x|
|. . .|x x x|x x x|
+-----+-----+-----+
Patterns from 40 maximal invalid patterns list (or "Magic" patterns) belong to anticorner patterns. So, 40 anticorner maximal invalid patterns are known. Recently Blue published a long list of maximal invalid patterns, 55 of them are anticorner patterns (see his posts in the thread Ask for patterns that they dont have puzzles 2). I'll add some patterns to this 95-patterns list to get full anticorner maximal invalid patterns.
From the practical point of view these maximal invalid patterns can be used to filter out impossible Sudoku clue configurations.
Serg
