The New Sudoku Players' Forum

[Bunnybuck]

Hi all, i just started sudoku for 2 days and i'm just wondering if anybody has come across any puzzle that is impossible to solve without trial and error?

For this puzzle, i think i've went through almost all the logical processes.

* * * * 7 * 9 * 8
* * * * * * * 3 2
5 * * 1 * * 6 * *
7 * * * * 2 * * *
* * 4 5 * 8 1 * *
* * * 6 * * * * 5
* * 2 * * 3 * * 9
9 8 * * * * * * *
4 * 7 * 5 * * * *

* 4 6 * 7 5 9 1 8
1 7 9 * * * 5 3 2
5 * 8 1 * 9 6 * *
7 * * * * 2 * * *
* * 4 5 * 8 1 * *
8 * * 6 * 7 * * 5
6 * 2 * * 3 * * 9
9 8 * * * * * * *
4 * 7 9 5 * * * *

From then on, the way i completed the puzzle was to fill in 1 of the 2 possible number for r1c1. Got to some problems 10 minutes later then used the 2nd possible number. Can anybody figure out a way to solve this without spending the 10 minute with trial and error? Thanks in advanced.

[angusj]

Have a closer look at r3c5

[Bunnybuck]

in box2, i have narrowed down my the possibility to

23 7 5
48 468 46
1 23 9

i still cannot see how to decide which number (2 or 3) to put in r3c5

[Animator]

Take a really good look at the number 1.

Where can it go in box 5?
What does this mean for box 8?
Where can it go in box 9?

What do you conclude out of the possible position of box 8 and box 9? As in, where can it go in box 7?

[Bunnybuck]

Thanks a lot animator, i see it now. I actually went through step 1,2 and 3 before, but failed to notice the last step in box7. Must be my clogged-up brain due to 4 consecutive hours of sudoku last night.

This game rocks

[Bunnybuck]

Hi all, i just started sudoku for 2 days and i'm just wondering if anybody has come across any puzzle that is impossible to solve without trial and error?

just wondering..

[simes]

Yes. (If you look through other threads in this forum, you'll find examples.)

[havingfun]

Bunnybuck,
Is this what you got?

3 4 6 2 7 5 9 1 8
3 4 6 2 7 5 9 1 8
1 7 9 8 6 4 5 3 2
5 2 8 1 3 9 6 4 7
7 5 1 3 4 2 8 9 6
2 6 4 5 9 8 1 7 3
8 9 3 6 1 7 4 2 5
6 1 2 4 8 3 7 5 9
9 8 5 7 2 1 3 6 4
4 3 7 9 5 6 2 8 1

[scrose]

That looks right -- minus the duplicate row 1, of course.

[IQ]

After some time, I ended up with that. This is a really hard sudoku!