The New Sudoku Players' Forum

by **P.O.** » Thu Jan 12, 2023 3:21 pm

Code: Select all: . . 8 3 . . . . . . . . . . 7 . . . . 4 3 9 8 5 2 . 6 . . 4 7 5 8 6 2 . . . 7 2 6 9 1 . . 2 . 6 4 3 1 5 . . 4 . 1 5 7 2 9 . . . . . . . . . 5 . . 7 . 8 . . . . . ..83..........7....439852.6..475862...72691..2.64315..4.15729.........5..7.8..... 15679 12569 8 3 124 46 47 1479 14579 1569 12569 259 16 124 7 348 13489 134589 17 4 3 9 8 5 2 17 6 139 139 4 7 5 8 6 2 39 358 358 7 2 6 9 1 348 348 2 89 6 4 3 1 5 789 789 4 368 1 5 7 2 9 368 38 3689 23689 29 16 149 346 3478 5 123478 3569 7 259 8 149 346 34 1346 1234

by **Cenoman** » Thu Jan 12, 2023 3:57 pm

Code: Select all: +------------------------+-------------------+--------------------------+ | 15679 12569 8 | 3 124 c46^ | d47 1479 14579 | | 1569 12569 259 | 16 124 7 | 348 13489 134589 | | 17 4 3 | 9 8 5 | 2 17 6 | +------------------------+-------------------+--------------------------+ | 139 139 4 | 7 5 8 | 6 2 39 | | 358 358 7 | 2 6 9 | 1 348 348 | | 2 89 6 | 4 3 1 | 5 789 789 | +------------------------+-------------------+--------------------------+ | 4 368 1 | 5 7 2 | 9 a368 a38 | | 3689 23689 29 | 16 149 346 | e3478 5 f23478-1 | | 3569 7 259 | 8 149 cb346^ |ca34^ a1346 f234-1 | +------------------------+-------------------+--------------------------+

Almost Y-Wing:
(1=3684)b9p2378 - (4)r9c6 = [(4=3)r9c7 - (3*=*6)r9c6 - (6=4)r1c6] - (4=7)r1c7 - r8c7 = (72)r89c9 => -1 r89c9; ste

by **SteveG48** » Thu Jan 12, 2023 5:23 pm

Code: Select all: *-----------------------------------------------------------------------------* | 15679 12569 8 | 3 124 46 | 4-7 1479 d14579 | | 1569 12569 259 | 16 124 7 | 348 13489 d134589 | | 17 4 3 | 9 8 5 | 2 d17 6 | *-------------------------+-------------------------+-------------------------| | 139 139 4 | 7 5 8 | 6 2 c39 | | 358 358 7 | 2 6 9 | 1 348 c348 | | 2 89 6 | 4 3 1 | 5 789 c789 | *-------------------------+-------------------------+-------------------------| | 4 368 1 | 5 7 2 | 9 368 c38 | | 3689 23689 29 | 16 149 346 |a3478 5 b123478 | | 3569 7 259 | 8 149 346 | 34 1346 1234 | *-----------------------------------------------------------------------------*

7r8c7 = r8c9 - (7=3489)r4567c9 - (3|4|8|9=157)b3p368 => -7 r1c7 ; ste

by **rjamil** » Thu Jan 12, 2023 6:13 pm

Simple two steps:

Code: Select all: +-------------------+--------------+---------------------+ | 15679 12569 8 | 3 124 46 | 47 1479 14579 | | 1569 12569 259 | 16 124 7 |(38)-4 13489 134589 | | 17 4 3 | 9 8 5 | 2 17 6 | +-------------------+--------------+---------------------+ | 139 139 4 | 7 5 8 | 6 2 39 | | 358 358 7 | 2 6 9 | 1 348 348 | | 2 89 6 | 4 3 1 | 5 789 789 | +-------------------+--------------+---------------------+ | 4 368 1 | 5 7 2 | 9 68-3 (38) | | 3689 23689 29 | 16 149 346 |(38)47 5 1247-38| | 3569 7 259 | 8 149 346 |(3)4 146-3 124-3 | +-------------------+--------------+---------------------+

1) ALP: 38 @ r89c7 r2c7 r7c9 => -3 @ r79c8 r9c9 => -38 @ r8c9 => -4 @ r2c7; NS 6 @ r7c8; and

Code: Select all: +-------------------+--------------+---------------------+ | 15679 12569 8 | 3 124 46 |*47 179-4 14579 | | 1569 12569 259 | 16 124 7 | 38 1389-4 134589 | | 17 4 3 | 9 8 5 | 2 *17 6 | +-------------------+--------------+---------------------+ | 139 139 4 | 7 5 8 | 6 2 39 | | 358 358 7 | 2 6 9 | 1 348 348 | | 2 89 6 | 4 3 1 | 5 789 789 | +-------------------+--------------+---------------------+ | 4 38 1 | 5 7 2 | 9 6 38 | | 3689 23689 29 | 16 149 346 | 378-4 5 1247 | | 3569 7 259 | 8 149 346 | 3-4 *14 124 | +-------------------+--------------+---------------------+

2) XY-Wing: 147 @ r39c8 r1c7 => -4 @ r12c8 r89c7; stte

R. Jamil

by **eleven** » Thu Jan 12, 2023 10:01 pm

SteveG48 wrote:7r8c7 = r8c9 - (7=3489)r4567c9 - (3|4|8|9=157)b3p368 => -7 r1c7 ; ste

Nice ! Even easier for me to see with the hidden quad:
7r8c7 = r8c9 - (7=3489)r4567c9 - r12c9 = 3489b3p1245 => -7r1c7

by **jco** » Fri Jan 13, 2023 11:54 am

7r8c7 = r8c9 - (7=3489)r4567c9 - (3|4|8|9=157)b3p368 => -7 r1c7 ; ste
Steve

Nice ! Even easier for me to see with the hidden quad:
7r8c7 = r8c9 - (7=3489)r4567c9 - r12c9 = 3489b3p1245 => -7r1c7

Nice! My favourite version of that idea is

(7=1)r3c8 - (1)r9c8 = (12-7)r89c9 = (7)r8c7 => -7 r1c7; ste

(exploiting the AHS (12)r89c9)

by **eleven** » Fri Jan 13, 2023 3:15 pm

Ah yes, there are simpler variants, another one is
7r8c7 = 721b9p698 - (1=7)r3c8 => -7r1c7; ste

by **Cenoman** » Fri Jan 13, 2023 3:21 pm

SteveG48 wrote:7r8c7 = r8c9 - (7=3489)r4567c9 - (3|4|8|9=157)b3p368 => -7 r1c7 ; ste

Same comment as others:
Nice !
I can't remember seeing already an AAAALS linked to an ALS by four restricted commons

by **P.O.** » Sat Jan 14, 2023 5:00 pm

thank you for your answers, my solution:

Code: Select all: 1r9c589 => r8c9 <> 7 r9c5=1 - r8n1{c45 c9} r9c8=1 - r3c8{n1 n7} - r6n7{c8 c9} r9c9=1 - c9n2{r9 r8} ste.

Puzzle 88