The New Sudoku Players' Forum

[ArkieTech]

Code: Select all

 *-----------*
 |..6|...|38.|
 |953|4..|.7.|
 |.7.|9..|24.|
 |---+---+---|
 |.6.|.95|...|
 |..8|2.4|9..|
 |...|61.|.5.|
 |---+---+---|
 |.45|..9|.1.|
 |.8.|..6|593|
 |.39|...|7..|
 *-----------*


Play/Print this puzzle online

[Leren]

Code: Select all

*--------------------------------------------------------------------------------*
| 4       2       6        |b157    a57      1-7      | 3       8       9        |
| 9       5       3        | 4       28      28       | 16      7       16       |
| 8       7       1        | 9       6       3        | 2       4       5        |
|--------------------------+--------------------------+--------------------------|
| 27      6       247      |d378     9       5        | 148     23      1278     |
| 5       1       8        | 2       3-7     4        | 9       36      67       |
| 3       9       247      | 6       1      e78       | 48      5       278      |
|--------------------------+--------------------------+--------------------------|
| 67      4       5        | 37      237     9        | 68      1       268      |
| 127     8       27       | 17      4       6        | 5       9       3        |
| 16      3       9        |c158     258     128      | 7       26      4        |
*--------------------------------------------------------------------------------*

(7=5) r1c5 - r1c4 = (5-8) r9c4 = r4c4 - (8=7) r6c6 => r1c6, r5c5 <> 7; stte

Leren

[eleven]

Either r18c4=17 or r1c4=5
r18c4=17->r7c4=3
r1c4=5->r1c6=7->r5c5=3
=>r4c4<>3
als xz: (3=5)r178-(5=3)r15c5 => r4c4<>3

[SudoQ]

(7=5) r1c5 - r1c4 = (5-8) r9c4 = r4c4 - (8=7) r6c6 => r1c6, r5c5 <> 7; stte

Similar pattern. Cell r1c5 need not be included.

Code: Select all

|-------------|---------------|---------------|
| 4    2  6   |(5)7-1 57 (17) | 3    8   9    |
| 9    5  3   | 4     28  28  | 16   7   16   |
| 8    7  1   | 9     6   3   | 2    4   5    |
|-------------|---------------|---------------|
| 27   6  247 |37(8) 9    5   | 148  23  1278 |
| 5    1  8   | 2    37   4   | 9    36  67   |
| 3    9  247 | 6    1   (78) | 48   5   278  |
|-------------|---------------|---------------|
| 67   4  5   | 37   237  9   | 68   1   268  |
| 127  8  27  | 17   4    6   | 5    9   3    |
| 16   3  9   |1(58) 258  128 | 7    26  4    |
|-------------|---------------|---------------|

/SudoQ

[RW]

Code: Select all

 *-----------------------------------------------------------*
 | 4     2     6     | 157   57    17    | 3     8     9     |
 | 9     5     3     | 4    *28   *28    | 16    7     16    |
 | 8     7     1     | 9     6     3     | 2     4     5     |
 |-------------------+-------------------+-------------------|
 | 27    6     247   | 378   9     5     | 148   23    1278  |
 | 5     1     8     | 2     37    4     | 9     36    67    |
 | 3     9     247   | 6     1     78    | 48    5     278   |
 |-------------------+-------------------+-------------------|
 | 67    4     5     | 37   #237   9     | 68    1     268   |
 | 127   8     27    | 17    4     6     | 5     9     3     |
 | 16    3     9     |#158  *258  *128   | 7     26    4     |
 *-----------------------------------------------------------*

UR (28) in r29c56: r7c5=2 or r9c4=8 must be true.

r7c5=2 => r2c5=8 => r9c5=5
r9c4=8 => r9c5=5

=> r9c5=5

[eleven]

How could i miss that?
When i tried it with the other external candidate 8, i saw, that it was invalid:
(8=37)r47-(7=1)r8c4-(1=28)r29c6 => r6c6<>8
These are the complementary cells of SudoQ's solution.

[ArkieTech]

ur(28)

I found:

Code: Select all

 *-----------------------------------------------------------*
 | 4     2     6     | 57-1  57   a17    | 3     8     9     |
 | 9     5     3     | 4     28    28    | 16    7     16    |
 | 8     7     1     | 9     6     3     | 2     4     5     |
 |-------------------+-------------------+-------------------|
 | 27    6     247   |c378   9     5     | 148   23    1278  |
 | 5     1     8     | 2     37    4     | 9     36    67    |
 | 3     9     247   | 6     1    b78    | 48    5     278   |
 |-------------------+-------------------+-------------------|
 | 67    4     5     |c37    237   9     | 68    1     268   |
 | 127   8     27    |c17    4     6     | 5     9     3     |
 | 16    3     9     | 158   258   28-1  | 7     26    4     |
 *-----------------------------------------------------------*
als xy-wing
(1=7)r1c6-(7=8)r6c6-(8=1)r478c4 => -1r1c4,r9c6

[daj95376]

An alternate way to view RW's solution.

Code: Select all

 +--------------------------------------------------------------+
 |  4     2     6     |  157   57    17    |  3     8     9     |
 |  9     5     3     |  4    *28   *28    |  16    7     16    |
 |  8     7     1     |  9     6     3     |  2     4     5     |
 |--------------------+--------------------+--------------------|
 |  27    6     247   |  378   9     5     |  148   23    1278  |
 |  5     1     8     |  2     37    4     |  9     36    67    |
 |  3     9     247   |  6     1     78    |  48    5     278   |
 |--------------------+--------------------+--------------------|
 |  67    4     5     |  37    237   9     |  68    1     268   |
 |  127   8     27    |  17    4     6     |  5     9     3     |
 |  16    3     9     |  158  *28+5 *28+1  |  7     26    4     |
 +--------------------------------------------------------------+
 # 47 eliminations remain

               | ----- external SIS ----- |
 (5=28)r92c5 - (2)r7c5 =28URr29c56= (8)r9c4  =>  r9c4<>5


[DonM]

I have a question:
I'm used to a system where everyone starts a solution from the same place in the puzzle eg. after the SSTS (Simple Sudoku Techiques Set) position. In the puzzles being posted daily here, is everyone running the original puzzle thru the same basic moves before solving the puzzle? And if so, what are they?

So far, if I have entered any solution here, I've been simply using someone else's grid that shows the puzzle with pencilling and no other solution marks in it.

Thanks for any info.

[ArkieTech]

I have a question:
I'm used to a system where everyone starts a solution from the same place in the puzzle eg. after the SSTS (Simple Sudoku Techiques Set) position. In the puzzles being posted daily here, is everyone running the original puzzle thru the same basic moves before solving the puzzle? And if so, what are they?

So far, if I have entered any solution here, I've been simply using someone else's grid that shows the puzzle with pencilling and no other solution marks in it.

Thanks for any info.

I provide a grid after locked candidate and locked set eliminations have been made in displaying a solution.

[daj95376]

I have a question:
I'm used to a system where everyone starts a solution from the same place in the puzzle eg. after the SSTS (Simple Sudoku Techiques Set) position. In the puzzles being posted daily here, is everyone running the original puzzle thru the same basic moves before solving the puzzle? And if so, what are they?

So far, if I have entered any solution here, I've been simply using someone else's grid that shows the puzzle with pencilling and no other solution marks in it.

Thanks for any info.

Hello Don,

Yes, everyone is using the same basic moves -- SSTS up to but not including X-Wing. This is a carry-over by those from Daily Sudoku.

Regards, Danny

[DonM]

Thanks Dan & Danny for the info.

[Leren]

Code: Select all

*--------------------------------------------------------------------------------*
| 4       2       6        |c157    b57      17       | 3       8       9        |
| 9       5       3        | 4       28      28       | 16      7       16       |
| 8       7       1        | 9       6       3        | 2       4       5        |
|--------------------------+--------------------------+--------------------------|
| 27      6       247      | 78-3    9       5        | 148     23      1278     |
| 5       1       8        | 2      a37      4        | 9       36      67       |
| 3       9       247      | 6       1       78       | 48      5       278      |
|--------------------------+--------------------------+--------------------------|
| 67      4       5        |c37      27-3    9        | 68      1       268      |
| 127     8       27       |c17      4       6        | 5       9       3        |
| 16      3       9        | 158     258     128      | 7       26      4        |
*--------------------------------------------------------------------------------*

Another als xy-wing solution:

(3=7) r5c5 - (7=5) r1c5 - (5=3) r178c4 => r4c4, r7c5 <> 3; stte

Leren

[Leren]

I have a question:
I'm used to a system where everyone starts a solution from the same place in the puzzle eg. after the SSTS (Simple Sudoku Techiques Set) position. In the puzzles being posted daily here, is everyone running the original puzzle thru the same basic moves before solving the puzzle? And if so, what are they?

So far, if I have entered any solution here, I've been simply using someone else's grid that shows the puzzle with pencilling and no other solution marks in it.

Thanks for any info.

Don,

I found the following definition of SSTS on the web today:

{Naked Single, Hidden Single, Naked Pair , Locked Candidates , Naked Triple , Naked Quad , Hidden Pair , Hidden Triple, Hidden Quad} , [ X-Wing , Swordfish , Simple Colors , Multi-Colors , XY-Wing ]

The moves in the curly brackets are what I understand to be "basics". The challenge of these threads appears to be to find a single non-basics move (after basics have been applied) after which the puzzle is solved with the only following moves being more basics but preferrably singles only. The terms in the square brackets are the elements of SSTS that would not be applied prior to "the move". If the full SSTS as above were applied then many of the puzzles in these threads would be solved within SSTS and there would be no challenge . The current puzzle would be a case in point - there some simple coloring moves that would complete it within SSTS. I also wouldn't include Jellyfish in basics.

Leren

[Marty R.]

Code: Select all

*--------------------------------------------------------------------------------*
| 4       2       6        |c157    b57      17       | 3       8       9        |
| 9       5       3        | 4       28      28       | 16      7       16       |
| 8       7       1        | 9       6       3        | 2       4       5        |
|--------------------------+--------------------------+--------------------------|
| 27      6       247      | 78-3    9       5        | 148     23      1278     |
| 5       1       8        | 2      a37      4        | 9       36      67       |
| 3       9       247      | 6       1       78       | 48      5       278      |
|--------------------------+--------------------------+--------------------------|
| 67      4       5        |c37      27-3    9        | 68      1       268      |
| 127     8       27       |c17      4       6        | 5       9       3        |
| 16      3       9        | 158     258     128      | 7       26      4        |
*--------------------------------------------------------------------------------*

Another als xy-wing solution:

(3=7) r5c5 - (7=5) r1c5 - (5=3) r178c4 => r4c4, r7c5 <> 3; stte

Leren

Same as leren, but I didn't know I was using an als xy-wing since I don't know what one is.

I wrote the third term of the notation as: (517=3)r187c4