The New Sudoku Players' Forum

by **urhegyi** » Sat Sep 18, 2021 9:58 am

Code: Select all: 1....8...26.9...3.5...4............2.7..8.1..4..5....6...6.4.5...3.....9.1...2...

by **marek stefanik** » Sat Sep 18, 2021 10:50 am

Code: Select all: .------------------.--------------------.-----------------------. | 1 349 479 | 237 a26–357 8 | 245679 24679 457 | | 2 6 478 | 9 157 157 | 4578 3 14578 | | 5 389 789 | 1237 4 1367 | 26789 126789 178 | :------------------+--------------------+-----------------------: | 389 589 15689 | 1347 f1367 1379–6| 345789 4789 2 | | 39 7 d26–59 |c234 8 e369 | 1 49 345 | | 4 289 1289 | 5 b1237 1379 | 3789 789 6 | :------------------+--------------------+-----------------------: | 789 289 289 | 6 1379 4 | 378 5 1378 | | 678 45 3 | 178 157 157 | 24678 124678 9 | | 6789 1 45 | 378 3579 2 | 34678 4678 3478 | '------------------'--------------------'-----------------------'

2r1c5 = r6c5 – r5c4 = (2–6)r5c3 = r5c6 – r4c5 = 6r1c5 – Loop => –357r1c5, –59r5c3 –6r4c6, btte

Marek

Website · by **denis_berthier** » Sat Sep 18, 2021 1:11 pm

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Code: Select all: Resolution state after Singles and whips[1]: +----------------------+----------------------+----------------------+ ! 1 349 479 ! 237 23567 8 ! 245679 24679 457 ! ! 2 6 478 ! 9 157 157 ! 4578 3 14578 ! ! 5 389 789 ! 1237 4 1367 ! 26789 126789 178 ! +----------------------+----------------------+----------------------+ ! 3689 589 15689 ! 1347 1367 13679 ! 345789 4789 2 ! ! 369 7 2569 ! 234 8 369 ! 1 49 345 ! ! 4 289 1289 ! 5 1237 1379 ! 3789 789 6 ! +----------------------+----------------------+----------------------+ ! 789 289 289 ! 6 1379 4 ! 2378 5 1378 ! ! 678 2458 3 ! 178 157 157 ! 24678 124678 9 ! ! 6789 1 45689 ! 378 3579 2 ! 34678 4678 3478 ! +----------------------+----------------------+----------------------+

Using only elementary rules with no undeclared steps:

Code: Select all: hidden-pairs-in-a-block: b7{n4 n5}{r8c2 r9c3} ==> r9c3≠9, r9c3≠8, r9c3≠6, r8c2≠8, r8c2≠2 whip[1]: r8n2{c8 .} ==> r7c7≠2 whip[1]: c3n6{r5 .} ==> r4c1≠6, r5c1≠6 finned-swordfish-in-rows: n5{r9 r5 r1}{c5 c3 c9} ==> r2c9≠5 z-chain[3]: c5n2{r6 r1} - b2n6{r1c5 r3c6} - c6n3{r3 .} ==> r6c5≠3 biv-chain[4]: r5n2{c3 c4} - c5n2{r6 r1} - b2n6{r1c5 r3c6} - r5n6{c6 c3} ==> r5c3≠5, r5c3≠9 hidden-single-in-a-row ==> r5c9=5 whip[1]: c9n3{r9 .} ==> r7c7≠3, r9c7≠3 hidden-pairs-in-a-row: r7{n1 n3}{c5 c9} ==> r7c9≠8, r7c9≠7, r7c5≠9, r7c5≠7 singles ==> r9c5=9, r9c3=5, r8c2=4, r4c2=5 biv-chain[4]: c5n2{r1 r6} - r5n2{c4 c3} - c3n6{r5 r4} - c5n6{r4 r1} ==> r1c5≠3, r1c5≠5, r1c5≠7 hidden-single-in-a-row ==> r1c7=5 hidden-triplets-in-a-block: b3{n2 n6 n9}{r1c8 r3c7 r3c8} ==> r3c8≠8, r3c8≠7, r3c8≠1, r3c7≠8, r3c7≠7, r1c8≠7, r1c8≠4 stte

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