The New Sudoku Players' Forum

by **eleven** » Sat Sep 11, 2021 4:00 pm

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

by **marek stefanik** » Sat Sep 11, 2021 7:46 pm

Code: Select all: .----------.---------------.----------------. | 7 9 4 | 2 3 5 | 1 8 6 | | 2 1 8 | 7 6 4 | 5 9 3 | | 3 6 5 | 9 18 18 | 4 2 7 | :----------+---------------+----------------: | 9 4 27 |b36 158 1278 |a267 35 128 | | 1 8 6 |b34 59 c27 | 9–27 35 c24 | | 5 3 27 | 46 189 1278 | 679–2 17 1248 | :----------+---------------+----------------: | 6 5 9 | 8 4 3 |a27 17 12 | | 8 7 1 | 5 2 6 | 3 4 9 | | 4 2 3 | 1 7 9 | 8 6 5 | '----------'---------------'----------------'

(27=6)r47c7 – (6=34)r45c4 – (4=27)r5c69 => –27r5c7, –2r6c7, stte

Marek

by **Leren** » Sat Sep 11, 2021 8:43 pm

Code: Select all: *---------------------------------------* | 7 9 4 | 2 3 5 | 1 8 6 | | 2 1 8 | 7 6 4 | 5 9 3 | | 3 6 5 | 9 18 18 | 4 2 7 | |--------+--------------+---------------| | 9 4 27 | 36 158 1278 | 267 35 128 | | 1 8 6 |d34 f5-9 27 |a279 e35 24 | | 5 3 27 |c46 189 1278 |b2679 17 1248 | |--------+--------------+---------------| | 6 5 9 | 8 4 3 | 27 17 12 | | 8 7 1 | 5 2 6 | 3 4 9 | | 4 2 3 | 1 7 9 | 8 6 5 | *---------------------------------------*

(9) r5c7 = (9-6) r6c7 = (6-4) r6c4 = (4-3) r5c4 = (3-5) r5c8 = (5) r5c5 => - 9 r5c5; stte

Leren

by **jco** » Sat Sep 11, 2021 9:09 pm

Code: Select all: .-------------------------------------------. | 7 9 4 | 2 3 5 | 1 8 6 | | 2 1 8 | 7 6 4 | 5 9 3 | | 3 6 5 | 9 18 18 | 4 2 7 | |----------+---------------+----------------| | 9 4 27 |b36 158 1278 |a267 b35 128 | | 1 8 6 | 34 d59 27 | 279 c35 24 | | 5 3 27 | 46 e189 1278 |f279-6 17 1248 | |----------+---------------+----------------| | 6 5 9 | 8 4 3 | 27 17 12 | | 8 7 1 | 5 2 6 | 3 4 9 | | 4 2 3 | 1 7 9 | 8 6 5 | '-------------------------------------------'

(6)r4c7 = (6-35)r4c48 = (5)r5c8 - (5=9)r5c5 - r6c5 = (9)r6c7 => -6 r6c7; ste
Edit: Using Medusa Colouring

Hidden Text: Show

by **eleven** » Sat Sep 11, 2021 9:42 pm

My one-stepper was the same as Marek's.

Code: Select all: *--------------------------------------------------------* | 7 9 4 | 2 3 5 | 1 8 6 | | 2 1 8 | 7 6 4 | 5 9 3 | | 3 6 5 | 9 #18 #18 | 4 2 7 | |-------------+--------------------+---------------------| | 9 4 27 | 36 #158 #1278 | 267 35 #128 | | 1 8 6 | 34 59 27 | 279 35 24 | | 5 3 27 | 46 #189 #1278 | 2679 *17 #1248 | |-------------+--------------------+---------------------| | 6 5 9 | 8 4 3 | 27 17 12 | | 8 7 1 | 5 2 6 | 3 4 9 | | 4 2 3 | 1 7 9 | 8 6 5 | *--------------------------------------------------------*

I liked this 18 UR r346c56,r46c9, which immediately places 1r6c8.
But it does not help so much.

Code: Select all: *------------------------------------------------------* | 7 9 4 | 2 3 5 | 1 8 6 | | 2 1 8 | 7 6 4 | 5 9 3 | | 3 6 5 | 9 18 18 | 4 2 7 | |-------------+--------------------+-------------------| | 9 4 27 | a36 158 1278 | a67 5-3 28 | | 1 8 6 | 34 b59 27 | b79 b35 24 | | 5 3 27 | 46 89 278 | 679 1 248 | |-------------+--------------------+-------------------| | 6 5 9 | 8 4 3 | 2 7 1 | | 8 7 1 | 5 2 6 | 3 4 9 | | 4 2 3 | 1 7 9 | 8 6 5 | *------------------------------------------------------*

Here the 18-UR also places 8r4c9, but i need something like
(3=67)r4c47 - (7=353)r5c758 => -3r4c8, stte

by **shye** » Sun Sep 12, 2021 2:29 am

Code: Select all: .----------.---------------.----------------. | 7 9 4 | 2 3 5 | 1 8 6 | | 2 1 8 | 7 6 4 | 5 9 3 | | 3 6 5 | 9 18 18 | 4 2 7 | :----------+---------------+----------------: | 9 4 27 |#36 18-5 1278 |#267 #35 128 | | 1 8 6 | 34 #59 27 |#279 3-5 24 | | 5 3 27 | 46 189 1278 | 2679 17 1248 | :----------+---------------+----------------: | 6 5 9 | 8 4 3 |#27 17 12 | | 8 7 1 | 5 2 6 | 3 4 9 | | 4 2 3 | 1 7 9 | 8 6 5 | '----------'---------------'----------------'

ALS y-wing
(5=9)r5c5 - (9=276)r457c7 - (6=35)r4c48
=> -5r4c5 -5r5c8 stte

by **totuan** » Sun Sep 12, 2021 3:07 am

Code: Select all: *-----------------------------------------------------------* | 7 9 4 | 2 3 5 | 1 8 6 | | 2 1 8 | 7 6 4 | 5 9 3 | | 3 6 5 | 9 18 18 | 4 2 7 | |-------------------+-------------------+-------------------| | 9 4 27 | 36 158 1278 | 267 35 128 | | 1 8 6 | 34 59 27 | 279 35 24 | | 5 3 27 | 46 189 1278 | 2679 17 1248 | |-------------------+-------------------+-------------------| | 6 5 9 | 8 4 3 | 27 17 12 | | 8 7 1 | 5 2 6 | 3 4 9 | | 4 2 3 | 1 7 9 | 8 6 5 | *-----------------------------------------------------------*

The same as eleven’s B, to avoid the empty cell (2679)r457c7 => (6)r4c7=(9)r5c7
(6)r4c7=(9)r5c7-(59=3)r5c58-r5c4=r4c4 => r4c4<>6, stte

Thanks for the puzzle.
totuan

Website · by **denis_berthier** » Sun Sep 12, 2021 5:01 am

.

Code: Select all: Resolution state after Singles and whips[1]: +----------------+----------------+----------------+ ! 7 9 4 ! 2 3 5 ! 1 8 6 ! ! 2 1 8 ! 7 6 4 ! 5 9 3 ! ! 3 6 5 ! 9 18 18 ! 4 2 7 ! +----------------+----------------+----------------+ ! 9 4 27 ! 36 158 1278 ! 267 1357 128 ! ! 1 8 6 ! 34 59 27 ! 279 357 24 ! ! 5 3 27 ! 46 189 1278 ! 2679 17 1248 ! +----------------+----------------+----------------+ ! 6 5 9 ! 8 4 3 ! 27 17 12 ! ! 8 7 1 ! 5 2 6 ! 3 4 9 ! ! 4 2 3 ! 1 7 9 ! 8 6 5 ! +----------------+----------------+----------------+ 66 candidates.

There are many 1-steppers using only bivalue chains:

The simplest require only length 5:

Code: Select all: biv-chain[5]: r4n3{c4 c8} - b6n5{r4c8 r5c8} - r5c5{n5 n9} - b6n9{r5c7 r6c7} - b6n6{r6c7 r4c7} ==> r4c4≠6 stte

Code: Select all: biv-chain[5]: r4c4{n3 n6} - b6n6{r4c7 r6c7} - b6n9{r6c7 r5c7} - r5c5{n9 n5} - b6n5{r5c8 r4c8} ==> r4c8≠3 stte

Code: Select all: biv-chain[5]: r5n5{c5 c8} - b6n3{r5c8 r4c8} - r4c4{n3 n6} - b6n6{r4c7 r6c7} - b6n9{r6c7 r5c7} ==> r5c5≠9 stte

Code: Select all: biv-chain[5]: r5c5{n5 n9} - b6n9{r5c7 r6c7} - b6n6{r6c7 r4c7} - r4c4{n6 n3} - b6n3{r4c8 r5c8} ==> r5c8≠5 stte

Code: Select all: biv-chain[5]: r4n6{c7 c4} - r4n3{c4 c8} - b6n5{r4c8 r5c8} - r5c5{n5 n9} - b6n9{r5c7 r6c7} ==> r6c7≠6 stte

Code: Select all: biv-chain[5]: r5n9{c7 c5} - r5n5{c5 c8} - b6n3{r5c8 r4c8} - r4c4{n3 n6} - b6n6{r4c7 r6c7} ==> r6c7≠9 stte

by **P.O.** » Sun Sep 12, 2021 7:37 am

Code: Select all: after singles: 7 9 4 2 3 5 1 8 6 2 1 8 7 6 4 5 9 3 3 6 5 9 18 18 4 2 7 9 4 27 d-3+6 158 1278 e2-67 1357 128 1 8 6 c+34 a-5×9 27 279 b-3+57 24 5 3 27 46 g18+9 1278 f2+67-9 17 1248 6 5 9 8 4 3 27 17 12 8 7 1 5 2 6 3 4 9 4 2 3 1 7 9 8 6 5 depth: 4 candidate: 9 from start ((5 0) (5 5 5) (5 9)) ((5 0) (5 8 6) (3 5 7)) ((3 1 10) (5 4 5) (3 4)) ((6 2 9) (4 4 5) (3 6)) ((6 3 1) (6 7 6) (2 6 7 9)) ((9 4 10) (6 5 5) (1 8 9)) ste.

The New Sudoku Players' Forum

C

C

Re: C

Re: C

Re: C

Re: C

Re: C

Re: C

Re: C

Re: C