The New Sudoku Players' Forum

[markf]

Hi all:
just discovered sudokus
really stuck on this one: any assistance and explanation would be greatly appreciated. thanks,
mark

782 *** *39
394 *7* *1*
615 9*3 4*7
*6* 1** 7**
*47 *** 95*
*** 7*9 *6*
438 267 195
*7* *** *46
**6 *** 37*

[r.e.s.]

That puzzle is invalid because it has more than one solution. Here are the first two of the 13 solutions found by gsf's program at http://www.research.att.com/~gsf/sudoku/ ...

Code: Select all

+-------+-------+-------+
| 7 8 2 | 4 1 5 | 6 3 9 |
| 3 9 4 | 8 7 6 | 5 1 2 |
| 6 1 5 | 9 2 3 | 4 8 7 |
+-------+-------+-------+
| 9 6 3 | 1 5 8 | 7 2 4 |
| 8 4 7 | 6 3 2 | 9 5 1 |
| 2 5 1 | 7 4 9 | 8 6 3 |
+-------+-------+-------+
| 4 3 8 | 2 6 7 | 1 9 5 |
| 5 7 9 | 3 8 1 | 2 4 6 |
| 1 2 6 | 5 9 4 | 3 7 8 |
+-------+-------+-------+

+-------+-------+-------+
| 7 8 2 | 4 1 6 | 5 3 9 |
| 3 9 4 | 8 7 5 | 6 1 2 |
| 6 1 5 | 9 2 3 | 4 8 7 |
+-------+-------+-------+
| 9 6 3 | 1 5 8 | 7 2 4 |
| 8 4 7 | 6 3 2 | 9 5 1 |
| 2 5 1 | 7 4 9 | 8 6 3 |
+-------+-------+-------+
| 4 3 8 | 2 6 7 | 1 9 5 |
| 5 7 9 | 3 8 1 | 2 4 6 |
| 1 2 6 | 5 9 4 | 3 7 8 |
+-------+-------+-------+

[markf]

ok thanks.
mark

[Shazbot]

check your numbers again - is it possible you misplaced one of the clues?

[markf]

I checked it again and those were the numbers. Thanks though but since then have been stuck on another one: I actually solved it but by fluke I realized later. Here's where I am:

x86 XX2 4XX
1X7 964 2XX
XX4 X8X 6XX
769 8XX 5XX
X4X X9X 8XX
X18 XX6 7X9
X71 6XX 9XX
XXX 179 3X6
693 428 157

I was able to eliminate 8 as a candiate from r7c8. But I can't make any further inferences. the sudocue program said there was a naked triple in box 3, with 3,5,8 but I thought 3 and 5 could appear in other boxes. I'm confused at the very least. I'm pretty sure if I could fill in one box I could solve it. When I did "solve" it I thought once I had done the elimination I wrote of above then 8 could only appear in the column 8 in row 8. I had somehow forgotten that it could be in r2c8 as well. It worked out but wasn't tremendously satisfying. Any nudges?

Any help would be greatly appreciated.

Thanks,
Mark

[markf]

x86 XX2 4XX
1X7 964 2XX
XX4 X8X 6XX
769 8XX 5XX
X4X X9X 86X
X18 XX6 7X9
X71 6XX 9XX
XXX 179 3X6
693 428 157

Basically I'm an idiot.
actually missed two clues, this after double checking it. the puzzle above is correct now.

mark

[SteveF]

I'm not sure what eliminations you have made from that point, but eg there is a naked pair in box 7 which allows some.

There are also some 'candidates locked to a column (or row)' eg column 2 and row 4.

However the one you really need to find is the hidden pair (or naked quad) in box 3 which allows eliminations and thus a placement in column 8.

[markf]

Thanks Steve, had seen the first things you mentioned but the hidden pair in box 3 jumped out when I wrote it out.

thanks for the nudge.

mark