The New Sudoku Players' Forum

[re'born]

Testing

OK so far.

Code: Select all

 . . . 1 2 3 . . .
 . . 4 . . . 5 . .
 6 7 . . . . . 1 8
 . . 3 . . . 4 . .
 . . . 5 . 1 . . .
 . . . . 8 . . . .
 . . . . 9 . . . .
 . . . 4 . 8 . . .
 . 1 6 . . . 9 3 .   SE=7.3



JPF

Forgive me for going off topic for a second, but your puzzle JPF is an excellent example of a couple of UR deductions that occur quite often but rarely seem to make much of a difference. After easy stuff, we get to

Code: Select all

.------------------.------------------.------------------.
| 59    59    8    | 1     2     3    | 67    4     67   |
| 1     3     4    | 8     6     7    | 5     29*   29*  |
| 6     7     2    | 9     4     5    | 3     1     8    |
:------------------+------------------+------------------:
| 25    8     3    | 26    7     9    | 4     256   1    |
| 2479- 2469% 79   | 5     3     1    | 8     2679- 2679*|
| 2579  2569  1    | 26    8     4    | 267   25679 3    |
:------------------+------------------+------------------:
| 247%  24%   57   | 3     9     6    | 1     8     257  |
| 3     29-   579  | 4     1     8    | 267   267   2567 |
| 8     1     6    | 7     5     2    | 9     3     4    |
'------------------'------------------'------------------'


where we can immediately deduce r5c1<>2 and r5c8<>2 using the potential deadly patterns in r57c12[24] and r25c89[29], respectively. For those keeping score at home, the first is type UR+3C/2SL, the second is type UR+2B/1SL. After this a finned x-wing (or alternatively a 2-string kite) forces r8c2<>2, and the puzzle is solved.

[JPF]

Forgive me for going off topic for a second, but your puzzle JPF is an excellent example of a couple of UR deductions that occur quite often but rarely seem to make much of a difference. After easy stuff, we get to...

Thanks rep'nA

Here's a clue :

Code: Select all

 . . . 1 2 3 . . .
 . . 4 . . . 5 . .
 6 7 . . . . . 1 8
 . . 3 . . . 2 . .
 . . . 5 . 1 . . .
 . . . . 3 . . . .
 . . . . 7 . . . .
 . . . 8 . 9 . . .
 . 1 6 . . . 7 5 .   SE=7.5



JPF

[JPF]

A new clue :

Code: Select all

 . . . 1 2 3 . . .
 . . 4 . . . 5 . .
 6 3 . . . . . 7 1
 . . 5 . . . 4 . .
 . . . 4 . 7 . . .
 . . . . 3 . . . .
 . . . . 5 . . . .
 . . . 8 . 1 . . .
 . 7 8 . . . 9 3 .   SE=8.2



JPF

[JPF]

I think it's time to give my last clue :

Code: Select all

 . . . 1 2 3 . . .
 . . 4 . . . 5 . .
 6 2 . . . . . 1 7
 . . 8 . . . 4 . .
 . . . 2 . 1 . . .
 . . . . 9 . . . .
 . . . . 8 . . . .
 . . . 5 . 7 . . .
 . 1 5 . . . 9 3 .    SE=8.5



JPF

[Eioru]

New pattern!

Code: Select all

...6.....
.7...5.2.
..2.3...9
9.....1..
..1.4...6
.8...2.5.
...7.....
.4...8.3.
..6.9...4

22 clues with
59 x Hidden Single

[JPF]

New pattern!

Thanks Eioru
It's not your turn...
... but who cares ?

I suspect that your pattern is a diagonal-like one.

Anyway, here's my quick first riposte :

Code: Select all

 . . . | 1 . . | . . .
 . 2 . | . . 3 | . 4 .
 . . 4 | . 5 . | . . 6
-------+-------+-------
 6 . . | . . . | 7 . .
 . . 7 | . 8 . | . . 1
 . 9 . | . . 5 | . 3 .
-------+-------+-------
 . . . | 4 . . | . . .
 . 6 . | . . 9 | . 5 .
 . . 1 | . 6 . | . . 8   SE= 9.2



JPF

[JPF]

Slight improvement :

Code: Select all

 . . . | 1 . . | . . .
 . 2 . | . . 3 | . 4 .
 . . 4 | . 5 . | . . 6
-------+-------+-------
 7 . . | . . . | 5 . .
 . . 8 | . 7 . | . . 1
 . 9 . | . . 5 | . 3 .
-------+-------+-------
 . . . | 4 . . | . . .
 . 6 . | . . 9 | . 5 .
 . . 1 | . 6 . | . . 8   SE= 9.5



JPF

[JPF]

a new improvement :

Code: Select all

 . . . | 1 . . | . . .
 . 2 . | . . 3 | . 1 .
 . . 4 | . 5 . | . . 6
-------+-------+-------
 7 . . | . . . | 8 . .
 . . 8 | . 7 . | . . 5
 . 4 . | . . 1 | . 7 .
-------+-------+-------
 . . . | 2 . . | . . .
 . 3 . | . . 9 | . 4 .
 . . 5 | . 6 . | . . 9    SE= 9.9



JPF

[ronk]

New pattern!

Code: Select all

...6.....
.7...5.2.
..2.3...9
9.....1..
..1.4...6
.8...2.5.
...7.....
.4...8.3.
..6.9...4

After reading JPF's "diagonal-like" comment, I decided to maximize symmetry and came up with:

Code: Select all

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

Your rows and columns were re-ordered to:
R: 3 1 2 5 4 6 9 7 8
C: 2 1 3 6 4 5 8 7 9

[JPF]

Thanks ronk

Here's a bad news :

Code: Select all

 . . . | 1 . . | . . .
 . 2 . | . . 3 | . 4 .
 . . 5 | . 6 . | . . 7
-------+-------+-------
 6 . . | . . . | 2 . .
 . . 7 | . 8 . | . . 9
 . 8 . | . . 4 | . 7 .
-------+-------+-------
 . . . | 7 . . | . . .
 . 3 . | . . 8 | . 6 .
 . . 1 | . 9 . | . . 5   SE= 10.5



it means that it will take hours now to test new puzzles...

Difficulty rating: 10,5
This Sudoku can be solved using the following logical methods:
55 x Hidden Single
4 x Naked Single
8 x Pointing
1 x Claiming
1 x Naked Pair
2 x X-Wing
1 x Hidden Pair
2 x Naked Triplet
1 x Hidden Triplet
1 x XYZ-Wing
1 x XY-Wing
1 x Unique Rectangle type 4
1 x Turbot Fish
1 x Forcing X-Chain
2 x Bidirectional Y-Cycle
5 x Forcing Chain
2 x Nishio Forcing Chains
4 x Region Forcing Chains
22 x Dynamic Contradiction Forcing Chains
4 x Dynamic Cell Forcing Chains
1 x Dynamic Double Forcing Chains
2 x Dynamic Region Forcing Chains
1 x Dynamic Cell Forcing Chains (+)
14 x Dynamic Contradiction Forcing Chains (+)
7 x Dynamic Contradiction Forcing Chains (+ Forcing Chains)
2 x Dynamic Region Forcing Chains (+ Forcing Chains)
Here is a diagonal-equivalent :

Code: Select all

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



JPF

[m_b_metcalf]

He loses his right if he doesn't propose any new puzzle within 1 week.

So, dear JPF, allow me to start a new pattern:

Code: Select all

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


As you will see, this has the outline of the Euro currency symbol. Thus, the First Prize will be an all-expenses-paid trip to the European Central Bank, with a tour by M. Trichet, and the right to take away as many 500-Euro notes as you can carry (to be confirmed).

Regards,

Mike Metcalf

[JPF]

As you will see, this has the outline of the Euro currency symbol.

OK,
Let's start slowly.

Here's a 7.1 € note :

Code: Select all

 . . 1 2 3 . 4 . .
 . . . . . . . 5 .
 . 6 . . . . . 7 .
 5 . 4 3 . . . . .
 . 7 . . . . . . .
 2 . 8 1 . . . . .
 . 5 . . . . . 9 .
 . . . . . . . 3 .
 . . 9 4 8 . 1 . .   ER=7.1


JPF

[m_b_metcalf]

OK,
Let's start slowly.

Agreed.

Code: Select all

 . . 7 4 3 . 6 . .
 . . . . . . . 9 .
 . 8 . . . . . 5 .
 4 . 2 6 . . . . .
 . 1 . . . . . . .
 5 . 3 8 . . . . .
 . 9 . . . . . 8 .
 . . . . . . . 4 .
 . . 6 7 2 . 3 .    SE 7.2


Regards,

Mike Metcalf

[JPF]

Code: Select all

 . . 1 2 3 . 4 . .
 . . . . . . . 5 .
 . 6 . . . . . 7 .
 7 . 3 6 . . . . .
 . 5 . . . . . . .
 2 . 8 1 . . . . .
 . 7 . . . . . 4 .
 . . . . . . . 8 .
 . . 9 3 8 . 1 . .    SE=7.3



JPF

[m_b_metcalf]

Code: Select all

 . . 1 2 3 . 4 . .
 . . . . . . . 5 .
 . 6 . . . . . 7 .
 7 . 3 6 . . . . .
 . 5 . . . . . . .
 2 . 8 1 . . . . .
 . 7 . . . . . 4 .
 . . . . . . . 8 .
 . . 9 3 8 . 1 . .    SE=7.3


Dear JPF, I'm having a problem getting beyond your €7.3. Here's another the same.

Code: Select all

 . . 1 2 3 . 4 . .
 . . . . . . . 5 .
 . 6 . . . . . 7 .
 5 . 4 3 . . . . .
 . 3 . . . . . . .
 2 . 6 1 . . . . .
 . 5 . . . . . 9 .
 . . . . . . . 3 .
 . . 2 4 8 . 1 . .      SE 7.3



Do you (or anyone else) have a tie-breaker?

Regards,

Mike Metcalf