The New Sudoku Players' Forum

by **udosuk** » Tue Jun 05, 2007 1:43 pm

claudiarabia wrote:
Code: Select all
. . . x . x . . . . x . . x . . x . . . . x . x . . . x . x . x . x . x . x . x . x . x . x . x . x . x . x . . . x . x . . . . x . . x . . x . . . . x . x . . .

The corner boxes left with one number in the middle.

Your pattern is equivalent to this:

Code: Select all: . x . x . x x . x x . x . x . . x . . x . x . x x . x x . x . . . . . . . x . . x . . x . x . x . . . . . . x . x . . . . . . . x . . x . . x . x . x . . . . . .

Where 2 corner boxes have 5 clues and 1 has 4 clues. :idea:

by **JPF** » Tue Jun 05, 2007 8:32 pm

This sub-pattern is valid as well :

Code: Select all: . . . | 1 . 2 | . . . . 3 . | . 4 . | . 1 . . . . | 5 . 6 | . . . -------+-------+------- 4 . 5 | . . . | 7 . 6 . 8 . | . . . | . 4 . 2 . 6 | . . . | 3 . 9 -------+-------+------- . . . | 9 . 5 | . . . . 2 . | . 8 . | . 7 . . . . | 2 . 3 | . . .

SE=8.4
24 clues, minimal

JPF

by **claudiarabia** » Fri Jun 15, 2007 7:10 pm

Hi,

what about this pattern?

Code: Select all: x . x . x . x . x . x . x . x . x . x . x . x . x . x . . . . . . . . . . x . . x . . x . . . . . . . . . . x . x . x . x . x . x . x . x . x . x . x . x . x . x

I wouldn't mind when you need more clues in the rows 1-3 7-9

by **JPF** » Fri Jun 15, 2007 8:26 pm

This pattern has obviously 2n solutions.
Here's an example with 2 solutions :

Code: Select all: 1 . 2 | . 3 . | 4 . 5 . 6 . | 7 . 1 | . 8 . 8 . 9 | . 2 . | 7 . 1 -------+-------+------- . . . | . . . | . . . . 3 . | . 4 . | . 2 . . . . | . . . | . . . -------+-------+------- 5 . 6 | . 8 . | 3 . 7 . 1 . | 4 . 3 | . 5 . 3 . 4 | . 6 . | 8 . 9

[Edit]
For the fun , here's one with 1000 solutions

Code: Select all: 1 . 2 | . 3 . | 4 . 5 . 3 . | 6 . 5 | . 1 . 5 . 7 | . 4 . | 8 . 3 -------+-------+------- . . . | . . . | . . . . 8 . | . 1 . | . 4 . . . . | . . . | . . . -------+-------+------- 8 . 4 | . 5 . | 3 . 6 . 5 . | 4 . 6 | . 7 . 6 . 1 | . 7 . | 9 . 4

[End Edit]

JPF

by **udosuk** » Sat Jun 16, 2007 5:57 am

JPF wrote:This pattern has obviously 2n solutions.

In case Claudia still doesn't see it, you can freely swap r4 & r6 in any solution. Therefore this pattern cannot give a unique solution.

by **Eioru** » Tue Jun 19, 2007 9:12 am

How about this one.

Code: Select all: x.x.....x .x..x.... x.x...x.. ...x.x... .x..x..x. ...x.x... ..x...x.x ....x..x. x.....x.x

Original:

Code: Select all: AAA...... AAA...... AAA...... ...AAA... ...AAA... ...AAA... ......AAA ......AAA ......AAA

Code: Select all: When there is 3 clues added, how many A can be taken? ... 4 ... , ... ? ... 5 ... , ... ? ... 6 ... , ... ?

by **JPF** » Tue Jun 19, 2007 9:38 am

The first pattern is easy ; you can even remove r5c5 :

Code: Select all: 1 . 2 | . . . | . . 3 . 4 . | . 5 . | . . . 3 . 6 | . . . | . . . -------+-------+------- . . . | 1 . 7 | . . . . 6 . | . . . | . 4 . . . . | 3 . 2 | . . . -------+-------+------- . . . | . . . | 3 . 2 . . . | . 8 . | . 6 . 9 . . | . . . | 4 . 7

JPF

by **m_b_metcalf** » Tue Jun 19, 2007 1:23 pm

Eioru wrote:Original:
Code: Select all
AAA...... AAA...... AAA...... ...AAA... ...AAA... ...AAA... ......AAA ......AAA ......AAA

Code: Select all
When there is 3 clues added, how many A can be taken? ... 4 ... , ... ? ... 5 ... , ... ? ... 6 ... , ... ?

Here are some quick results that set lower bounds not necessarily limits:

Code: Select all: 6 . . . . . 4 . . . . . . . . . 1 . . . . . . 8 . 5 3 . . . . 4 1 6 . . . . . . 5 . . . . . . 3 . . 9 . . . 1 7 8 3 . . . . . 9 . . . . . . . . 4 6 . . . . . . 5 With 6 added, remove 13 [Edit: Spurred on by JPF, we improve by 2.]

Code: Select all: . . . . . . 6 8 5 . . . . . . . 4 1 . . . . . 2 . . . . . . . 3 . 8 . . . . . 1 5 9 . . . . . 6 . 7 . . . . 8 . . 4 . . . . . 2 3 7 . . . . . . . 5 1 . . . . . 7 With 5 added, remove 11 [Edit: Spurred on by JPF, we improve by 2.]

Code: Select all: . . . . . . 2 1 4 . . . . . . . . 6 . . . . . 8 . 5 9 . . . 6 . 5 3 . . . . . 3 9 4 . . . . . 2 1 . . . . . 8 6 . 5 . . . . . 3 . . . . . . . . 4 1 7 . . . . . . With 4 added, remove 9 [Edit: Further improvement, by 1.]

Of course, putting the added cells in different positions could well change the results, as would any requirement to maintain symmetry.

Regards,

Mike Metcalf

by **JPF** » Tue Jun 19, 2007 3:55 pm

14+6=20 :

Code: Select all: 1 . . | . . . | . . . 2 . . | . 3 . | . 4 . . 5 6 | . . . | . . . -------+-------+------- . . . | 7 . . | . . . . 7 . | 8 6 . | . . 5 . . . | . 4 5 | . . . -------+-------+------- . . . | . . . | . . 7 4 . . | . 2 . | . . 6 . . . | . . . | 5 1 8

13+6=19 :

Code: Select all: 1 . 2 | . . . | . . . . . . | . 3 . | . . . 4 . 5 | . . . | . 1 . -------+-------+------- . . . | 5 . 1 | . . 2 . 6 . | . . . | . . . . . . | 7 . 8 | . . . -------+-------+------- . . . | . . . | 5 . 3 . . . | . . . | . 7 . . 9 . | . 2 . | 4 . 6

14+5=19 :

Code: Select all: 1 . . | . . . | . . . 2 . . | . 3 . | . . . 4 5 6 | . . . | . . . -------+-------+------- . . . | 4 . . | . . . . 7 . | 5 . . | . 8 . . . . | 6 2 1 | . . . -------+-------+------- . . . | . . . | 6 . . . 3 . | . 8 . | . . . . . . | . . . | 4 9 2

13+5=18 :

Code: Select all: 1 . . | . . . | . . . 2 . . | . 3 . | . . . 4 5 6 | . . . | . . . -------+-------+------- . . . | 4 . . | . . . . 7 . | 5 . . | . 3 . . . . | 6 . 1 | . . . -------+-------+------- . . . | . . . | 6 . . . 3 . | . 8 . | . . . . . . | . . . | 4 5 9

JPF

by **JPF** » Tue Jun 19, 2007 6:37 pm

17+4=21 :

Code: Select all: 1 . . | . . . | . . . 2 3 . | . 4 . | . . . 5 6 7 | . . . | . . . -------+-------+------- . . . | 5 . . | . . . . . . | 7 8 . | . 4 . . 5 . | 3 2 6 | . . . -------+-------+------- . . . | . . . | 5 . . . . 9 | . . . | . 8 . . . . | . . . | 6 7 1

19+3=22 :

Code: Select all: 1 2 3 | . . . | . . . 4 5 6 | . . . | . . . 7 . . | . . . | . . . -------+-------+------- . . . | 1 . 4 | . 7 . . 8 . | 2 . . | . . . . . . | 7 6 5 | . . . -------+-------+------- . . . | . . . | 4 . . . . . | . 3 . | 6 . 9 . . . | . . . | 1 2 5

JPF

by **Eioru** » Mon Jun 25, 2007 8:38 pm

Original / Example1 / Example2 / Unknown

Code: Select all: **.....** .*.....*. .*.....** **.....** **.....** **.....** *......** **.....** ....*.... ....*.... ....*.... ....*.... ...*.*... ...*.*... ...*.*... .....*... ..*...*.. ..*...*.. ..*...*.. ..*...*.. ...*.*... ...*.*... ...*.*... ...*..... ....*.... ....*.... ....*.... ....*.... **.....** **.....** **......* **.....** **.....** .*.....*. **.....*. **.....**

Take any four or more clues from four corners of original pattern.
I think they might be difficult to find and have more Pointing with ER rating.
Last patten, which only has 6 pattern in the middle, I don't have seen yet.

by **JPF** » Mon Jun 25, 2007 10:14 pm

Eioru wrote:Last patten, which only has 6 pattern in the middle, I don't have seen yet.

Code: Select all: 1 2 . . . . . 3 4 3 5 . . . . . 6 2 . . . . 7 . . . . . . . . . 4 . . . . . 3 . . . 8 . . . . . 2 . . . . . . . . . 5 . . . . 7 6 . . . . . 4 8 5 4 . . . . . 9 7

The other patterns are easy.
For example :

Code: Select all: . 1 . . . . . 2 3 4 . . . . . . 5 6 . . . . 5 . . . . . . . 3 . 2 . . . . . 4 . . . 7 . . . . . 1 . 8 . . . . . . . 6 . . . . 9 3 . . . . . . 4 5 2 . . . . . 3 .

SE=7.2

JPF

by **Mauricio** » Mon Jun 25, 2007 10:59 pm

Impressive work!, JPF
The remaining pattern:

Code: Select all: . 1 . . . . . 2 . 2 3 . . . . . 4 1 . . . . 5 . . . . . . . 1 . 6 . . . . . 7 . . . 8 . . . . . 4 . 3 . . . . . . . 9 . . . . 9 4 . . . . . 1 7 . 7 . . . . . 6 . ER 8.8

BTW, I tried to create a sudoku with 19 clues or less and horizontal+vertical symmetry, unsuccesfully. Can anyone help me?

by **claudiarabia** » Tue Jun 26, 2007 1:52 pm

Mauricio wrote:Impressive work!, JPF
The remaining pattern:
Code: Select all
. 1 . . . . . 2 . 2 3 . . . . . 4 1 . . . . 5 . . . . . . . 1 . 6 . . . . . 7 . . . 8 . . . . . 4 . 3 . . . . . . . 9 . . . . 9 4 . . . . . 1 7 . 7 . . . . . 6 . ER 8.8

BTW, I tried to create a sudoku with 19 clues or less and horizontal+vertical symmetry, unsuccesfully. Can anyone help me?

An outstanding sudoku. That is the first puzzle I see, the Explainer is using only advanced ramificated forcing chains to solve it. No ordinary forcing chain!

Claudia

by **claudiarabia** » Tue Jun 26, 2007 2:01 pm

JPF wrote:This pattern has obviously 2n solutions.
Here's an example with 2 solutions :

Code: Select all
1 . 2 | . 3 . | 4 . 5 . 6 . | 7 . 1 | . 8 . 8 . 9 | . 2 . | 7 . 1 -------+-------+------- . . . | . . . | . . . . 3 . | . 4 . | . 2 . . . . | . . . | . . . -------+-------+------- 5 . 6 | . 8 . | 3 . 7 . 1 . | 4 . 3 | . 5 . 3 . 4 | . 6 . | 8 . 9
...
[End Edit]

JPF

Finally I've seen it. A nice puzzle. I'm still unfamiliar with solving multisolutional sudokus. But I'm glad to find an unsolvable pattern for you.

The New Sudoku Players' Forum

Ask for some patterns that they don't have puzzles.

Re: Mission impossible?