*------------------------------------*
| 7 24 6 | 3 24 9 | 1 5 8 |
|a234 234 5 | 8 7 1 | 6 2-4 9 |
| 8 9 1 | 24 5 6 | 3 7 d24 |
|-----------+-----------+------------|
| 356 356 8 | 7 369 4 | 29 1 26 |
|b346 7 9 | 1 36 2 | 5 8 c46 |
| 1 46 2 | 5 69 8 | 49 3 7 |
|-----------+-----------+------------|
| 29 1 3 | 249 24 7 | 8 6 5 |
| 69 8 7 | 69 1 5 | 24 24 3 |
| 256 256 4 | 26 8 3 | 7 9 1 |
*------------------------------------*
*-------------------------------------*
| 7 24 6 | 3 24 9 | 1 5 8 |
| 23-4 234 5 | 8 7 1 | 6 d24 9 |
| 8 9 1 | 24 5 6 | 3 7 c24 |
|------------+-----------+------------|
| 356 356 8 | 7 369 4 | 29 1 26 |
|a346 7 9 | 1 36 2 | 5 8 b46 |
| 1 46 2 | 5 69 8 | 49 3 7 |
|------------+-----------+------------|
| 29 1 3 | 249 24 7 | 8 6 5 |
| 69 8 7 | 69 1 5 | 24 24 3 |
| 256 256 4 | 26 8 3 | 7 9 1 |
*-------------------------------------*
Sudoku123456789 wrote:I found the the same ER can lead to -4R5C9
Sudoku123456789 wrote:It is actually the same ER, but the other way around (ERI = R2C9, strong link 4 R2C1 = R2C5) -->) -R4C9
Side question: how do I note a strong link on a single digit in the same row/collum?
Leren wrote:Sudoku123456789 wrote:It is actually the same ER, but the other way around (ERI = R2C9, strong link 4 R2C1 = R2C5) -->) -R4C9
Side question: how do I note a strong link on a single digit in the same row/collum?
OK I see it now but the elimination is - 4 r5c9 and there is a column Strong link (4) r2c1 = (4) r5c1.
In Eureka notation Strong links are usually denoted by an equal sign and (for brevity) you don't have to repeat a digit in the middle of a chain unless it changes.
You could have written this as an X chain : (4) r3c9 = r2c8 - r2c1 = (4) r5c5 => - 4 r5c9
Leren
Sudoku123456789 wrote : (4) r3c9 = r2c8 - r2c1 = (4) r5c1 => - 4 r5c9 I guess we're both human