The New Sudoku Players' Forum

[Fortesque92]

https://postimg.cc/hJvQgWFH

[Hajime]

Without computer help:

If r1c1=2 then r6c1<>2
If r1c1<>2 then follow the "2" on/off along rows and columns
via box1 box3 box9 box7 box1 (twice) box4
where r6c1<>2 also

So r6c1=3

[Leren]

Code: Select all

.34....6.......9....9..48.556..27.......8...2.........9......4.8..3..6...7.25....

Code: Select all

*----------------------------------------------*
|a27    3   4   | 58   9   58  |b27   6    1   |
| 167   8   5   | 167  367 2   | 9    37   4   |
| 1267  1-2 9   | 167  367 4   | 8    237  5   |
|---------------+--------------+---------------|
| 5     6   18  | 49   2   7   | 134  189  389 |
| 13    49  17  | 4569 8   356 | 1457 1579 2   |
| 23    49  278 | 459  1   35  | 457  5789 6   |
|---------------+--------------+---------------|
| 9    d25  36  | 678  67  1   |c25   4    38  |
| 8     125 12  | 3    4   9   | 6    25   7   |
| 4     7   36  | 2    5   68  | 13   189  389 |
*----------------------------------------------*

Skyscraper of 2's in cells a-b-c-d => - 2 r3c2

Leren

[Fortesque92]

God damn it, I spent about 40 minutes looking at this one to find a skyscraper! haha. Cheers.