Wasn't able to complete it by myself. But noticed a funny thing at around 7:05 regarding col 6. The four missing values are 3, 4, 6, & 9 (not 2, 3, 4, & 9). So I don't see how you can eliminate '6' from cell R7-C6 at that point.
After starting to watch your videos im improving my sudokus. Gettig fanatic with my daily NYT hard puzzle :)! But with this one i didnt manage to find the 19 pair... After reading the comments on this video, i found it and was able to solve (cheating a bit haha). Im actually relieved you and many people in the comments also find this one difficult:). Thanks for the daily explanation!
Really tough one for me today, but got there in the end after the hidden corner marked 3s in box 2. Used nearly all of the "Rangsk rules" for solving: 1. Geometry 2. Don't lose momentum 3. NYT trick (sometimes not all are given) 4. Hidden triples 5. Sometimes you have to pencil everything 6. Uniqueness traps (error checking)
I spotted the 19 pair as a NYT trick 189 triple in column four. Took me two attempts though, restarted because I filled the grid with pencilmarks and couldn't see a thing!
I found a combination of 1's and 9's in box 4 en box 7 eliminate a 8 in cell R2C4 and give a hidden 19's , same as below. 31 minutes. Normal my time is from 11 to 20 minutes to solve a NYS.
Did he get lucky that at 25:52 was a 7. he said it was a naked 7 but there where 2 spots in the bottom right corner box that the 7 could have been in and in the same box he placed the 8 there where 2 other spots the 7 could have been in. im just confused if it wasnt a lucky mistake that how he deduced it to being a 7? EDIT: i see the logic. you were just going to fast for me to catch it. you didnt unmark the 7 from the 25 pair in the corner.
First kind comment ... spoiler below the fold. - - - - - - This was indeed another tricky one. My solution was different because of my more extensive pencil marking. I got the 1,9 pair in c4 by --- you'll hate me for this :) -- finding a naked 3,4,5,7 quad in r4c4, r5c4, r6c4, and r8c4. The revealed the 8 in r1c4 and -- significantly -- let me corner-mark the 3s in r1c5 and r2c5. Those pointed down and, together with the 3's in c4 of box5, let me place the 3 in r9c6. That 3 forced the 9 in box2 (r3c6) that resolved the 1,9 pair in c4. That, in turn, left a 3,4 pair in r1c5 and r2c5. That took a pencil-marked 4 from r9c4 and created a 6,7 pair in r9 (r9c5 and r9c8). That pair collapsed r9c1 to a 5, and the rest of my solve collapsed from there. My time was 35 min, but I also broke the puzzle on my first try. This was truly fun. I loved how you found the 1,9 pair in c4 -- I have to get better at finding hidden pairs that way. That was much easier than seeing the quad in a sea of pencil-marks. Another really fun puzzle, and another really informative solve from you.
@@Rangsk : Indeed. I suspect that there are only a few solution paths through a harder sudoku like this. While the logic of hidden pair vs naked quad is complementary, I would still like to get better at your technique of finding hidden pairs.
@@thomasstambaugh5181 I've called it "given-centric scanning" before, but settled on just "geometry". You look at how the known digits restrict the board. I saw the 1 and 9 in box 5 and got suspicious. I do this all the time but most of the time it's not quite enough, but when you do spot it it's a great feeling!
I found a quad in row 3 and got one digit but the puzzle kept fighting...a couple pairs later and it collapsed. I never found that hidden 19 you got. Challenging puzzles the last few days!! Thanks as always.
A way of finding hidden triples. If three givens are in a box and avoid a row (or column, I'll just use row here though), then those three digits need to go somewhere in that row. If the row already has three givens placed outside the box that don't match the three in the box, then those three digits must go in the three remaining open cells.
@@RaniMeer Do you mean the naked 7 in box 7 around 25:48? If so, it was the only digit left for that cell. Can't be 123459 from the box or 68 from the row..
@@Rangsk bottom right box there where 2 spots in the same row the 7 could have been. also in the same box you placed the 7 there where 2 other spots the 7 could have been. and in the column there was also 2 other spots marked where the 7 could have been. the 68 was from the box next to that box. but the box next to that one in the corner had 2 open spots for the 7
OKAY i seed the logic you just didnt unmark it that the corner box was a 25 pair the 7 was still marked in it as a 257, thats where the confusion was.@@Rangsk
At 7:01 you state that "the remaining digits are 2,3,4 and 9" in column 6, presumably, which is how you notate that cell (C6R8) as a 4. But the remianing digits are 3,4,6 and 9. It could have been a 6, or am I missing something?
Dude! You missed a very important point in solving this sudoku. Indeed, this puzzle is very difficult, I fucked with it for a long time, because I solve sudoku without pencil marks. It's much more difficult, but more interesting. Look, after the 6th minute, when you found "1" (R4C6), it immediately became obvious that in column # 4, the pair 1-9 can only be in two places: R2C4 and R7C4. After that, we find 8 (R1C4). And then everything is obvious. Bye. Good luck!
Like almost everyone else, I found this one tricky to start with. Kudos for spotting that 19 pair. Awesome. Thanks for your daily videos.
25:31 to solve. Very difficult I would say. The 19 pair was very hard to spot and there was still some work after that.
Wasn't able to complete it by myself. But noticed a funny thing at around 7:05 regarding col 6. The four missing values are 3, 4, 6, & 9 (not 2, 3, 4, & 9). So I don't see how you can eliminate '6' from cell R7-C6 at that point.
lol yeah that was a mistake I caught like 10 seconds later...
After starting to watch your videos im improving my sudokus. Gettig fanatic with my daily NYT hard puzzle :)! But with this one i didnt manage to find the 19 pair... After reading the comments on this video, i found it and was able to solve (cheating a bit haha). Im actually relieved you and many people in the comments also find this one difficult:). Thanks for the daily explanation!
This was a tough one. I sruggled from the word 'Go'. Really interesting how you solve it, especially without using XY wing etc. With pure logic.
Really tough one for me today, but got there in the end after the hidden corner marked 3s in box 2. Used nearly all of the "Rangsk rules" for solving:
1. Geometry
2. Don't lose momentum
3. NYT trick (sometimes not all are given)
4. Hidden triples
5. Sometimes you have to pencil everything
6. Uniqueness traps (error checking)
I love this summary!
This was tricky! Thanks Rangsk!
Tough one. Kudos for spotting that 19 hidden pair
I spotted the 19 pair as a NYT trick 189 triple in column four. Took me two attempts though, restarted because I filled the grid with pencilmarks and couldn't see a thing!
Difficult, but appropriate for the ides of March!
I found a combination of 1's and 9's in box 4 en box 7 eliminate a 8 in cell R2C4 and give a hidden 19's , same as below. 31 minutes. Normal my time is from 11 to 20 minutes to solve a NYS.
Box 2
This was the hardest NYT puzzle I’ve seen since I started about 3 months ago 😹😹
Thank you for this comment. I've been doing them about as long and thought I'd gotten pretty good at the hards until today!
Yeah, this one was tough!
Sensei solved the puzzle but I retreated
Yeah this one was weird how it grinded to a halt for me a few times
Did he get lucky that at 25:52 was a 7. he said it was a naked 7 but there where 2 spots in the bottom right corner box that the 7 could have been in and in the same box he placed the 8 there where 2 other spots the 7 could have been in. im just confused if it wasnt a lucky mistake that how he deduced it to being a 7?
EDIT: i see the logic. you were just going to fast for me to catch it. you didnt unmark the 7 from the 25 pair in the corner.
After finding the big 1 in box 5 ....., there is a NYT-trick in column 4...
A 189 triple is to see.
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First kind comment ... spoiler below the fold.
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This was indeed another tricky one. My solution was different because of my more extensive pencil marking. I got the 1,9 pair in c4 by --- you'll hate me for this :) -- finding a naked 3,4,5,7 quad in r4c4, r5c4, r6c4, and r8c4. The revealed the 8 in r1c4 and -- significantly -- let me corner-mark the 3s in r1c5 and r2c5. Those pointed down and, together with the 3's in c4 of box5, let me place the 3 in r9c6. That 3 forced the 9 in box2 (r3c6) that resolved the 1,9 pair in c4. That, in turn, left a 3,4 pair in r1c5 and r2c5. That took a pencil-marked 4 from r9c4 and created a 6,7 pair in r9 (r9c5 and r9c8). That pair collapsed r9c1 to a 5, and the rest of my solve collapsed from there. My time was 35 min, but I also broke the puzzle on my first try.
This was truly fun. I loved how you found the 1,9 pair in c4 -- I have to get better at finding hidden pairs that way. That was much easier than seeing the quad in a sea of pencil-marks. Another really fun puzzle, and another really informative solve from you.
Your solve actually sounds similar! The hidden 19 vs naked 3457 is expected because they are essentially two ways of seeing the same logic :)
@@Rangsk : Indeed. I suspect that there are only a few solution paths through a harder sudoku like this. While the logic of hidden pair vs naked quad is complementary, I would still like to get better at your technique of finding hidden pairs.
@@thomasstambaugh5181 I've called it "given-centric scanning" before, but settled on just "geometry". You look at how the known digits restrict the board. I saw the 1 and 9 in box 5 and got suspicious. I do this all the time but most of the time it's not quite enough, but when you do spot it it's a great feeling!
I did it this way too!
I found a quad in row 3 and got one digit but the puzzle kept fighting...a couple pairs later and it collapsed. I never found that hidden 19 you got. Challenging puzzles the last few days!! Thanks as always.
What is an NYT trick? Thanks!
A way of finding hidden triples. If three givens are in a box and avoid a row (or column, I'll just use row here though), then those three digits need to go somewhere in that row. If the row already has three givens placed outside the box that don't match the three in the box, then those three digits must go in the three remaining open cells.
Thank you so much!
At 26:00 how did you get the 7 no logics here
Did you link the correct timestamp? This is near the end of the puzzle.
Just before that 26:00. Thanks for responding
@@RaniMeer Do you mean the naked 7 in box 7 around 25:48? If so, it was the only digit left for that cell. Can't be 123459 from the box or 68 from the row..
@@Rangsk bottom right box there where 2 spots in the same row the 7 could have been. also in the same box you placed the 7 there where 2 other spots the 7 could have been. and in the column there was also 2 other spots marked where the 7 could have been. the 68 was from the box next to that box. but the box next to that one in the corner had 2 open spots for the 7
OKAY i seed the logic you just didnt unmark it that the corner box was a 25 pair the 7 was still marked in it as a 257, thats where the confusion was.@@Rangsk
Hard one.
kind comment
At 7:01 you state that "the remaining digits are 2,3,4 and 9" in column 6, presumably, which is how you notate that cell (C6R8) as a 4. But the remianing digits are 3,4,6 and 9. It could have been a 6, or am I missing something?
You just didn't watch for a few more seconds before commenting this (this was a mistake in my scanning and I corrected it shortly after)
Dude! You missed a very important point in solving this sudoku. Indeed, this puzzle is very difficult, I fucked with it for a long time, because I solve sudoku without pencil marks. It's much more difficult, but more interesting.
Look, after the 6th minute, when you found "1" (R4C6), it immediately became obvious that in column # 4, the pair 1-9 can only be in two places: R2C4 and R7C4. After that, we find 8 (R1C4). And then everything is obvious. Bye. Good luck!
Did I miss that, or did you just not watch to the end of the video? 17:58