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by **champagne** » Sun Nov 23, 2025 10:38 am

trying to split puzzles in two groups, with TH and without TH, I have several puzzles looking like this one rating skfr 11.0

12....7..6.9..751..5719.2.6.16...9.57.5.196..29.65.17.......8.1....4.3......8.45.

Code: Select all: 1 2 348 |3458 36 34568 |7 3489 3489 6 348 9 |2348 23 7 |5 1 348 348 5 7 |1 9 348 |2 348 6 --------------------------------------------- 348 1 6 |23478 237 2348 |9 2348 5 7 348 5 |2348 1 9 |6 2348 2348 2 9 348 |6 5 348 |1 7 348 --------------------------------------------- 3459 3467 234 |23579 2367 2356 |8 269 1 589 678 128 |2579 4 1256 |3 269 279 39 367 123 |2379 8 1236 |4 5 279

all have the fully given row or column as here column 7
and 2 more of the 3 "potential TH" digits as here 48r89c5

I see no TH threat here
should be a common pattern to explain this high rating

by **totuan** » Sun Nov 23, 2025 3:33 pm

Code: Select all: *---------------------------------------------------------------------* | 1 2 #48+3 | 3458 36 34568 | 7 3489 3489 | | 6 a348 9 | 2348 #2+3 7 | 5 1 a348 | | b348 5 7 | 1 9 b348 | 2 #48+3 6 | |-----------------------+----------------------+----------------------| |b#48+3 1 6 | 23478 237 2348 | 9 2348 5 | | 7 a348 5 |#248+3 1 9 | 6 2348 2348 | | 2 9 ab348 | 6 5 b348 | 1 7 a#48+3 | |-----------------------+----------------------+----------------------| | 3459 3467 234 | 23579 2367 2356 | 8 269 1 | | 589 678 128 | 2579 4 1256 | 3 269 279 | | 39 367 123 | 2379 8 1236 | 4 5 279 | *---------------------------------------------------------------------*

The same marek’s here, whichever (3|4|8)r1c3 => (3|4|8)’s at #-marked cells => +3’s at marked cells, stte

Thanks for the puzzle!
totuan

by **ghfick** » Sun Nov 23, 2025 5:55 pm

Hi champagne and totuan,
I am trying to flow totuan's technique. I might call it a cell forcing chain where the starter cell is r1c3. I am unable to see that the digit 3 is placed in several cells no matter whether r1c3 is 3, 4 or 8. The 3 placements are not easy (for me). Do the 3 placements require advanced steps with each value for r1c3 assigned?

by **totuan** » Sun Nov 23, 2025 6:40 pm

Hi Gordon,

Code: Select all: *--------------------------------------------------------------------* | 1 2 A348 | 3458 36 34568 | 7 *3489 *3489 | | 6 348& 9 | 2348 23 7 | 5 1 b348& | |*348# 5 7 | 1 9 348# | 2 a348 6 | |----------------------+----------------------+----------------------| | 348# 1 6 | 23478 237 2348 | 9 2348 5 | | 7 348& 5 | 2348 1 9 | 6 2348 2348 | | 2 9 *348&# | 6 5 d348# | 1 7 c348& | |----------------------+----------------------+----------------------| | 3459 3467 234 | 23579 2367 2356 | 8 269 1 | | 589 678 128 | 2579 4 1256 | 3 269 279 | | 39 367 123 | 2379 8 1236 | 4 5 279 | *--------------------------------------------------------------------*

Let X be the digit in r1c3:
01: r1c3=X => *-marked cells r1c89,r3c1,r6c3<>X => X’s: abcd => r3c6<>X => in R3 r3c8=X
02: Oddagon &-marked cells => at least one of r5c2,r6c9 must contain X's => r5c9<>X => in C9 r6c9=X
03: Oddagon #-marked cells => r4c1=X
04: (2)&(3) => in B5 r5c4=X => in B2 r2c5=X
In cases X=(4|8) then impossible by empty cell in B2 or B5 => X=3

This can call: marek's pattern

totuan

by **champagne** » Mon Nov 24, 2025 10:55 am

Hi gordon and totuan,

I also had to do some home work to understand the solution.
I'll come back later to totuan wording, I am not familiar with the oddagon pattern.

Here is the way I see it
marek defines any solution as 'a,b,c' for the spllt of the 3 digits 348

Code: Select all: 1 2 a |5bc 36 56bc |7 9bc 9bc 6 b 9 |2ac 23 7 |5 1 ac c 5 7 |1 9 ab |2 ab 6 --------------------------------------------- 348 1 6 |23478 237 2348 |9 2348 5 7 348 5 |2348 1 9 |6 2348 2348 2 9 348 |6 5 348 |1 7 348 --------------------------------------------- 3459 3467 234 |23579 2367 2356 |8 269 1 589 678 128 |2579 4 1256 |3 269 279 39 367 123 |2379 8 1236 |4 5 279

This gives 2 possibilities

=======================================

Code: Select all: 1 2 a |5bc 36 56bc |7 9bc 9bc 6 b 9 |2ac 23 7 |5 1 ac c 5 7 |1 9 ab |2 ab 6 --------------------------------------------- b 1 6 |27ac 237 2ac |9 2ac 5 7 a 5 |2bc 1 9 |6 2bc 2bc 2 9 c |6 5 ab |1 7 ab --------------------------------------------- 3459 3467 234 |23579 2367 2356 |8 269 1 589 678 128 |2579 4 1256 |3 269 279 39 367 123 |2379 8 1236 |4 5 279

the double sky scraper ab ab ab ab leads to a conflict 'a'
======================================================
second with the skyscraper 'a' same places

Code: Select all: 1 2 a |5c 36 56c |7 9b 9b 6 b 9 |2a 23 7 |5 1 c c 5 7 |1 9 b |2 a 6 --------------------------------------------- a 1 6 |27bc 237 2c |9 2bc 5 7 c 5 |2ab 1 9 |6 2ab 2ab 2 9 b |6 5 ac |1 7 ac --------------------------------------------- 3459 3467 234 |23579 2367 2356 |8 269 1 589 678 128 |2579 4 1256 |3 269 279 39 367 123 |2379 8 1236 |4 5 279

if r1c3 # 3 then b or c is 3,
quick conflict, here for 'c' in column 9

Code: Select all: 1 2 a |5c 36 56c |7 9b 9b 6 b 9 |a 2 7 |5 1 c c 5 7 |1 9 b |2 a 6 --------------------------------------------- a 1 6 |27bc 237 2c |9 2bc 5 7 c 5 |2b 1 9 |6 2ab 2ab 2 9 b |6 5 a |1 7 c

r1c3=3 ....

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