The New Sudoku Players' Forum

[SteveG48]

Apparently Marty wasn't kidding - the BUG+6 move can be found here. I didn't check it but I assume it is correct.

Leren

Leren, I wouldn't have been able to find that if I had tried. I didn't post the six lines of notation to prove it, rather I got lazy and assumed the reader would trust me. But I just now reviewed it and it's correct. A fun puzzle, to be sure.

Very nice, Marty. It is, indeed, correct, and I've learned something from it.

[SteveG48]

Code: Select all

 *--------------------------------------------------*
 | 28   9    78   | 6    5    47   | 34   23   1    |
 | 25   4    3    | 8    1    9    | 7    26   56   |
 | 1    6    57   | 3    2    47   |*459  49   8    |
 *----------------+----------------+----------------|
 | 6    3    1    | 2    49   5    | 8    49   7    |
 | 57   57   4    | 1    69   8    | 2    36   39   |
 | 9    28   28   | 7    46   3    | 1    5    46   |
 *----------------+----------------+----------------|
 | 4    1    25   | 59   7    6    |*359  8   *239  |
 | 78   78   9    | 45   3    2    | 6    1    45   |
 | 3    25   6    |*459  8    1    |*459  7    29   |
 *--------------------------------------------------*


OK, so here's what I learned from looking at Marty's BUG+6 solution. It's similar to a Kraken solution in which each possibility leads to the desired conclusion.
Looking at the current puzzle we get:

BUG+5 => 4r3c7 or 5r7c7 or 9r9c7 or 9r7c9 or 5r9c4 must be true.

The first 3 are actually correct singles solutions to the puzzle so chains can be constructed to any valid deletion. Left as an exercise.


Looking at the last 2,

9r7c9 - (9=25)r7c34 - (2=78)r16c3 - (7=4)r1c6
(5-4)r9c4 = r9c7 - r1c7 = 4r1c6

Therefore, BUG+5 => r1c6=4 ; stte