What a crazy day! My brother had his PhD Defense today, one of my best friends had his birthday whom I visited and now the feature too. Just incredible.

@davidrattner9

8 ай бұрын

Congrats on your day today!! You are a genuis!! Absolutely astonishing and much respect for how you set this!!

@leporid257

8 ай бұрын

is it Klappstuhl for easy folding after understanding the mechanism?

@kathyjohnson2043

8 ай бұрын

Congratulations to you and your brother and Happy Birthday to your friend! 🎉

This is the kind of puzzle which is MILES away from my abilities. These kind of logics just doesn't seem to click with my brain at all. It's a reminder of how brilliant Simon truly is, despite of all the times he has us shouting at him for not doing obvious sudoku while solving sudoku puzzles.

This is one of those puzzles where I very much enjoyed watching Simon solve it, and am glad I didn't attempt it myself

@sealed2mybff

8 ай бұрын

Oh no. I'm just starting, and already wondering what the junk I'm gonna do...

@longwaytotipperary

8 ай бұрын

@@sealed2mybff😆

24:35 sorry Simon, there is a much simpler reason this doesn't work : 2+3+4 = 9 and there must be two nines in the column !

@nataslia2490

8 ай бұрын

I actually did it the exact same way as Simon haha. I don’t know why i noticed that before two nines having to be placed in that column 😂

@RichSmith77

8 ай бұрын

"My brain's done it. Well done brain." Proceeds to show his brain missed the easy explanation. 🙂

@LAaronB10

8 ай бұрын

He had JUST proved that the row 5 could not be the row with no 1s or 9s in the middle box. Column 8 was under identical constraints. I was really surprised he did not immediately realize that.

@RichSmith77

8 ай бұрын

@@LAaronB10 Not quite. He hadn't concluded that for row 5 yet. He had looked at two possibilities separately. (i) That there was a sandwich spanning the middle box, and (ii) there wasn't a sandwich spanning the middle box. It was only while considering option (ii) specifically, that he concluded the empty row in the middle box couldn't be in row 5. He still thought that a sandwich spanning the central box could be in row 5. (He sums it up at 20:17, and specifically still includes a span in row 5 as a possibility at 20:23). It's only five minutes later, at 25:48, after getting r5c1 as a 9, that he realises the three cell sandwich cannot span box 5 in row 5.

@bobh6728

8 ай бұрын

Simon amazes me again. The sandwich can’t span the middle of row 5 nor column 8, because the smallest it could be is 2,3,4 making the clue (first cell of the row/column) a nine which clashes with crust. But Simon somehow determines that if the sandwich did span the box it would have to have a 5, making it impossible.

There's a 2nd step after the breakin that was missed, @45:00, which could have made things much easier. Green & yellow are different pairs with the same sum. Either 25 & 34 or 26 & 35. Both options use 2 AND 3. r6c7 sees all of green and yellow, and so can't be 2 or 3, and so must be 4. And that means 4 isn't in yellow or green, so it is 26 & 35 and orange is 8. Simon did the 2nd part to establish orange is 8, but skipped the part where orange being 8 means yellow & green are a 2356 quartet.

@keineangabe8993

8 ай бұрын

Yes, was shouting the same at my TV 😂

"ICHTUES" actually translates to "I do it", if anyone cares 😅😂 looking forward to the puzzle, rules look pretty promising ♥

@TheFrogfather1

8 ай бұрын

After many classes at the Goethe Institut and more than a year of Duolingo I really should have known that :(

@elizabethswann05

8 ай бұрын

​@@TheFrogfather1 I'm a nativ german and didn't realize it until I red this comment, if that helps you xD

a three-cell sandwich spanning the central box of row 5 or column 8 fails at first glance, because the 9 in the sandwich crust clashes with the 9 in the sandwich clue (and therefore the first box of the row/column

Corpsing is not “acting like a corpse”, it’s to “do the worst possible thing while _playing_ a corpse”, i.e.: burst out laughing, usually.

Amazing news: Ren's new album just hit the #1 spot in the UK album chart! Right, with that out of the way, time to watch the video...

Loved the break-in on this one. I found very quickly that numbers less than nine in the triple sandwich clues forced a single cell sandwich into the last box they affected, and that meant only one of those clues could be less than nine, which felt really satisfying to discover, from there it was just eliminating nine for the top clue, and everything fell into place nicely for the start. 48:02

Rules: 05:25 Let's Get Cracking: 07:05 What about this video's Top Tier Simarkisms?! Bobbins: 1x (40:27) Knowledge Bomb: 1x (07:49) Three In the Corner: 1x (1:05:39) And how about this video's Simarkisms?! Hang On: 18x (08:38, 08:38, 08:43, 16:44, 16:46, 17:43, 17:43, 17:43, 17:46, 24:51, 30:19, 31:30, 32:36, 40:57, 40:57, 56:33) Sorry: 15x (12:09, 16:51, 21:16, 28:17, 28:17, 28:17, 28:20, 31:13, 45:29, 45:46, 45:46, 45:46, 56:50, 1:01:07, 1:01:18) Ah: 15x (08:38, 17:43, 26:43, 29:51, 33:40, 33:40, 40:51, 45:29, 54:46, 54:46, 57:26, 58:01, 1:04:59, 1:05:05, 1:05:10, 1:05:13) That's Huge: 9x (24:47, 32:38, 51:09, 54:48, 54:48, 58:55, 1:03:51) Brilliant: 6x (01:40, 01:49, 53:18, 53:20, 58:31, 1:07:56) In Fact: 6x (09:44, 25:55, 29:57, 34:19, 41:28, 43:18) By Sudoku: 5x (37:26, 41:58, 44:03, 1:02:11, 1:04:11) Stuck: 4x (40:30, 40:31, 45:29, 45:33) Come on Simon: 4x (45:46, 48:01, 49:23, 56:33) What on Earth: 3x (40:22, 40:35, 45:49) The Answer is: 3x (22:07, 36:36, 48:37) Naughty: 3x (46:30, 1:03:32, 1:03:34) Ridiculous: 3x (37:51, 37:51, 1:07:32) Progress: 3x (00:32, 16:54, 1:00:45) Pencil Mark/mark: 3x (31:01, 32:10, 50:45) Clever: 2x (58:05, 1:07:03) Beautiful: 2x (01:45, 03:16) Incredible: 2x (01:00, 1:07:00) Obviously: 2x (09:29, 36:52) What Does This Mean?: 2x (16:02, 55:38) Cake!: 2x (04:13, 04:40) Good Grief: 1x (23:21) Goodness: 1x (20:53) Bother: 1x (1:03:23) Missing Something: 1x (53:24) In the Spotlight: 1x (1:05:42) Lovely: 1x (03:54) Fascinating: 1x (1:07:37) Elegant: 1x (01:24) Inarticulate: 1x (13:15) Magnificent: 1x (1:07:05) I've Got It!: 1x (23:17) Stunning: 1x (01:37) Box Thingy: 1x (59:43) Pregnant pause: 1x (39:28) Wow: 1x (50:11) Bar Humbug: 1x (52:09) Baffling: 1x (01:31) Fabulous: 1x (02:44) Most popular number(>9), digit and colour this video: Eighteen (6 mentions) One (128 mentions) Orange (17 mentions) Antithesis Battles: High (5) - Low (1) Even (2) - Odd (0) Outside (4) - Inside (0) Row (64) - Column (30) FAQ: Q1: You missed something! A1: That could very well be the case! Human speech can be hard to understand for computers like me! Point out the ones that I missed and maybe I'll learn! Q2: Can you do this for another channel? A2: I've been thinking about that and wrote some code to make that possible. Let me know which channel you think would be a good fit!

wasn't sure what to do this evening. been watching the channel for years and considering becoming a patron for a while, I guess it's time to put myself to the test and try and finish the hunt in the next three hours before midnight...

@niiii_niiii

8 ай бұрын

Best of luck!!!!❤

@slushpuppydevil

8 ай бұрын

@@niiii_niiii thank you! Currently bashing my brain into puzzle 4 it feels so close to breaking through but I can't quite see it. Going to be a challenge to get to puzzle 9 in time!

@niiii_niiii

8 ай бұрын

@@slushpuppydevil I believe in you!!! 6 minutes to midnight here ❤️💪💪💪💪

@slushpuppydevil

8 ай бұрын

Thankyou so much haha@@niiii_niiii ! unfortunately it wasn't to be. But I've had a great night of non stop puzzling and I'm excited to (hopefully) finish it over the rest of the weekend

@niiii_niiii

8 ай бұрын

@@slushpuppydevil well that's great!!! I can only do regular sudokus so far, I can't understand the advanced break-ins yet. But I love doing them and I will advance slowly haha

The inability to enter the numbers in the circles outside the board really hurts. Immensely frustrating watching Simon place the 4 in box 6 then fail to complete that sandwich with known total until several minutes later.

@AhsimNreiziev

8 ай бұрын

If I put my "programmer-brain" on, I suspect (though I can't be sure) that making it possible to put digits into the arrow-bulbs would have meant essentially making the grid a 10x10, which in turn (again this is my suspicion) would have meant that the server-side software wouldn't have recognised the *3 In The Corner* _(tm, Cracking The Cryptic) (also Losing Its Religion)_ . And that this was the reason the people who put the puzzle into the software decided to make the arrow-bulbs un-targetable.

@remybeauchamp

8 ай бұрын

A suggestion should be made to whomever can get it done. We sent someone to the moon with much less technology at our disposal!

"Sie haben den Klappstuhl ausgegraben!" - "Jetzt drehns völlig durch..." :-D

24:11 That would also put two 9's in column 8, which is how I determined the impossibility.

i just watched that 25 minutes sudoku and now this... it's a blessing, truly

At a first glimpse, this is pure madness. It's one of those mathematical questions where you are asked to solve a problem with way too little information. But you start to investigate and are able to find restriction after restriction and are finally able to fit it in a pure logical field. The person who created this is really a genius. This is art of the highest kind. And watching Simon's struggling to reach the solution was not just pure joy but also inspiring. As a math teacher one of my hardest tasks is to invite students to really take on this kind of struggling. And I will further on encourage them to watch Cracking the Cryptic videos. 10/10. Actually speachless.

I think Simon needs a new keyboard, because his present keyboard has done many weird things lately.

What a mind-bend! Took me *forever* to figure out how to think about this puzzle at all. Once I did it moved okay. Didn't get anywhere near Simon's time, of course. Terrific puzzle, thanks to Simon and ICHTUES!

Loved it! One of those where there's half an hour of staring then it clicks and flows fantastically.

I agree that it would have made things much clearer to follow your solve, and I can well imagine to solve it oneself, if it were possible to put the sandwich clues in the circles. It would have made me quite confused and caused the same thought process to happen over and over, to wit, "What is my goal in this column?" and then have to look obliquely ... that is unfortunate, and the only blemish on a wonderful puzzle! And what a solve - thank you so much, Simon, for doing this puzzle, I found it quite interesting, absorbing really, to watch you work though the options. I was able in my own little brain to discard 2, 3, and 4 from being a sandwich clue anywhere, but it took much more effort to work out the rest. Loved it.

@JohnRandomness105

8 ай бұрын

Not quite. The sandwich clue on column 5 was 2.

@emilywilliams3237

8 ай бұрын

ah yes, it was! @@JohnRandomness105

Well done Simon’s brain! And Simon’s patience and good humor throughout! My brain says its taking a nap - worn out from trying to keep up. 😴

"and we might say 'that's fine' except it's not quite" sounded very Tom Scott-esque to me at 24:20 hahaha. Brilliant puzzle and solve as always

Usually, I don't care whether the coloring is completed (or even removed entirely) at the end, but the red/orange/yellow/green is a perfect match for fall foliage season in my area, so that was an extra level of "aw, that's sweet"

If we consider r5c1, the number X in this cell is written as a sandwich-clue in rows 4, 5 and 6. Row 5 cannot have a single-digit sandwich, because otherwise the number X would appear twice, namely in r5c1 and between 1 and 9. Means: 1 and 9 in row 5 must be at least two cells apart and X must be able to be described as the sum of two different numbers. The following is valid: X > 4. Furthermore, we are forced to write 1 and 9 in two different boxes in row 5, because otherwise 1 and 9 cannot be two cells apart. If we now look at box 4, we realize that there is no single-digit sandwich there either, because then the number X would be in box 4 twice. To the number X: The number 5 can be described here only with [2,3] or [5], since 1 and 9 are not usable. It is further valid: For 6: [2,4] or [6]. For 7: [2,5], [3,4] or [7]. For 8: [2,6], [3,5] or [8]. For 9: [2,7], [3,6], [4,5] or [2,3,4]. Analogously, this all applies to r1c8 and we name the number in there Y. Now to Box 5: Logically, we can only write one 1 and 9 there. This means that at least one row has no 1 and 9 in Box 5, but this row must still contain a sandwich. It is either (1) a single-digit sandwich in Box 6 or (2) a three-digit sandwich, which extends completely over Box 5 (and X would be 9). But if we have case (1), we have a conflict (23:40). Therefore we have case (2) and X is 9. We don't have the same conflict with r1c8 in Box 6 and Box 9, because there is no break for the single-digit sandwich in Box 9.

Great solve Simon!! Love seeing your admiration for these setters!

@longwaytotipperary

8 ай бұрын

Ditto!

An incrediblely well-set puzzle. While at times I wasn't completely sure of some of the logical jumps, I am glad I had such a stalwart guide through the Sudoku miasma (or is that fog? Haha...) Fantastically well solved, Simon, and kudos to ICHTUES.

It would be interesting to know the name of the testers. I totally agree that they _"do an incredible job."_ And they have been doing it for as long as I can remember. Almost 100% of the puzzles featured on *CTC* are mind-blowingly excellent 👏👏👏👏

@AhsimNreiziev

8 ай бұрын

I agree it would be interesting to know the testers' names, but at the same time I imagine they wish to remain anonymous (otherwise we'd probably know at least some of their names by now), and I believe that is fully their right, and that we should respect that right.

If I may offer a tip: to keep track of which sandwich clues have been used, I use the pen tool to mark them with a red "X" on the edge of the grid.

@remybeauchamp

8 ай бұрын

Great idea! Until we get the option to fill out the boxes outside of the grid and why not, have the option to color them!

I love when I'm really excited that I have found something and when Simon sees it, his response is "oh well that was obvious" 😅😂

82 minutes. And at the start my brain was just melting, after you figured out how to start it's not so hard, just need to spot different things, but the start is just something!

This one took me 82 minutes but today I'm just proud to be able to say I finished it.

What a break-in. I'm still not through it, but it's very cool.

very very nice puzzle, managed to do it in 42 minutes, but the interaction between rows 456 and cols 789 was marvelous!

I'm sitting here shouting "you can't have a sum that spans 3 columns in box 5! Where will the 9 go?"

Tricky but manageable! Thank you setter!

whew... glad I ended my attempt at this puzzle after 15 mins when I couldn't even come close to finding out where to start... wow this is a toughy!

I love the colour combination used today Very plaisante to watch

Let's hope this sudoku folds for you once you find the brilliant break-in!

I kinda hope there is a merch option that says, in a big friendly font, “Well done, brain!”

Klappstuhl is what we called sandwiches in my grandparents home, which is quite fitting. For reference, my grandparents spoke Kashubian language.

One given digit and some arrows outside the grid... What?! Oh boy. This oughta be good Edit: I was right, it *was* good

This took me a long stare and entering some examples to figure out the logic, and then: the aha moment! Gotta stay very alert throughout, not getting confused between those circles and arrows!

Absolutely brilliant puzzle! And a more incredible solve. I beat Simon to the 1,9 pair in box9, but I got thoroughly stuck right after.

Interesting idea. No real scratching your head with this one. The general direction is almost immediately clear, but it takes a while to work through the possibilities until you get the initial bunch of 1s and 9s in place.

Classic unique break-in. This is one of those puzzles that if I didn't absolutely know for sure it was solvable, I'd said within 5 minutes there's not nearly enough information.

Was so focused on getting 3 in the top right corner, the bottom left corner surprised me!!!

Took a couple of hours but I got it done. This was a really cool puzzle.

Wow!! - What a puzzle. It took me about 90 minutes to break in so I restarted my clock and managed to complete it in 1:04:35. Really chuffed with finishing it unaided thanks to my ever improving skills learned from this channel!

48:43 finish. I did sandwich coloring, which helped with the start. But it definitely was not the easiest puzzle I've solved lately. Very fun, excellent!

Ooh, this is a great one!

Simon jumped over why orange can’t be 9 quite fast took me a minute

24:39 So funny because Simon is showing row 8 with a 9 sandwich sum, which has to go in row 1, but sandwich ends in rows 3 and 7. The 9 can't be in row 1 and row 3 or 7. But he's going back to the horizontal sum for the middle rows can't be 2, 3, or 4.

Unrelated to the video - but a feature request for the app. I regularly go back to past sudokus to try and beat my time, but it's rather laborious to have to go back all the way to the puzzle selection screen to see my record time. Could it be shown on the pause screen? Also, after you beat your best time, it shows the new time and new record (which is identical), but not the old record. It would be nice to see the 'previous best' to know by how much I've improved. I can't be the only one who's competitive with themselves, surely. It would make my enjoyment of the app that much greater! Thanks.

Wow above my level. Normal I solve them in a time that is 3 or 4 times longer. But this one was to complicated. 👍well done ✅

16:00 Highlighting both the row and the column gave me the hint I needed to continue. It took me a very long time, but I finally broke the puzzle, sigh. 46:00 This point in the grid, my conclusion about a certain digit/circle breaks the puzzle here. I found where I'd made an unwarranted assumption, and then finally (slowly) solved the puzzle.

That break-in was insane. I thought I had completely lost my mind. 47:52 in the end

Very interesting puzzle! Love this quote "well done brain". I did watch "Kingsman" and I thought that Harry (Colin Firth) resembles someone, and that's you! Not twins, but he was a smart character and maybe because he is british, but I did think of you, Simon, when I watched the movies (1 and 2). 🤗

solved in 45, but did need Simon's help to figure out the break in. Fun

At the 40 minute mark, what is stopping the 9 in box r5c1 and the 7,8 in box r1c8 from switching places and swapping all the other numbers from vertical to horizontal?

@AnnaVahtera

8 ай бұрын

This is definitely what I want to know. There's nothing in Simon's initial logic that couldn't translate to the columns instead of rows. I think Simon just got incredibly lucky (not the first time this happens) by starting from rows and not columns.

@SeanTBarrett

8 ай бұрын

​@@AnnaVahtera No, the logic doesn't translate. The quick summary of what's stopping them from switching places and swapping all the other numbers is that they aren't symmetric in the grid. Boxes 4,5,6 and 3,6,9 are similar, but they intersect in the third horizontal box and the second vertical box, so you can't just swap them, there's no actual swapping possible. Details: It's true that the two sets of boxes 4,5,6 and 3,6,9 have the same pattern of sandwich numbers. One of the basic things proved is that the middle row/column must have 1 or 9 in the middle box of each set; this is true for both. (Simon, being Simon, actually solves this a different way the second time, but it's still true.) So r5 must have a 1 or 9 in box 5, and c8 must have a 1 or 9 in box 6. Thus far, they're equivalent. The 9 in r5c1 is forced by the fact it can't have a 1-cell sandwich fully contained in box 6, because of the existence of c8's 1/9 in box in 6 preventing r4/r6 from having both a 1 and a 9. Without a 1-cell sandwich, this forces the 3-cell sandwich in r4 or r6, thus forcing the 9 in r5c1. But there is no equivalent pressure on c8 from r5. c8's 1/9 in box 6 affects r5, but r5's 1/9 in box 5 doesn't affect c8. So there's no proof that r1c8 has to be a 9, but there is a proof that r5c1 has to be a 9.

@AnnaVahtera

8 ай бұрын

@@SeanTBarrett So.. that makes it just worse? You're left with MORE possibilities to continue, not LESS. So Simon starting with rows instead of columns was a massive stroke of luck. If he started from the columns and applied the same logic, he'd get half an our in the puzzle, then have to essentially "start over" from the rows perspective and continue from there?

@SeanTBarrett

8 ай бұрын

@@AnnaVahtera I guess in theory, but either he wouldn't have gotten very far on the columns, or he probably would have figured the same thing out just from the perspective of the columns. It wouldn't have taken much longer. I thought you were agreeing with the person you were replying to that the logic literally could be swapped over and the focus in my answer was just on explaining why the logic isn't swappable ("Why couldn't you use the EXACT same logic Simon used in the three rows for the three columns?") not how you'd make progress if you started there.

@AnnaVahtera

8 ай бұрын

@@SeanTBarrett No, I mean the logic just for the three central rows, without taking into account anything in the columns. The same logic Simon applies to the central rows can be applies to the last three columns. Identically, until the point Simon includes anything outside the three rows. That's the first 10-20minutes of the solve (I don't remember when it was that he referenced them the first time.) I wouldn't say 15% to 30% of the total solve time is an insignificant time. Try it, if you start from the columns and apply the same logic Simon did until the point he references anything outside the rows. You can perfectly apply that to the columns. Because the clues at the start of the rows are identical to the clues at the start of the columns. You can get quite far that way. I'd say the first 15 minutes or so of the solve could be applied to the columns and nothing else would change.

they dug up the Klappstuhl.

50:35 - the 4 is given because you can place a 4 in R6C7 as soon as you notice that that cell sees both versions of the 2/3 pair (green and yellow), which removes a 4 from R5C9, making the 4 in R5 in either C2 or C3... so the given 4 shows you which way round it goes.

20:53 for me, I found the break-in pretty quickly (around 14 minutes in), and the rest flowed very quickly after that

59:14 No, that cell is a 5 because it has to add with the 4 to make 9. That would have helped with the "smooth" solving! :)

klapsztula means sandwich with 2 pieces of bread klapped together

23:22 for me. Absolutely fantastic puzzle!!

@CrackingTheCryptic

8 ай бұрын

HOW?? That is another of your absolutely amazing times!!

Ah! What I saw is that a 234 on column 8 adds to 9, but we already have 9 doing the sandwiching in another place along the column.

lovely one

Incredible puzzle! You can actually get that 4 in r6c7 waaay earlier than Simon did, by noticing that whether r1c8 is a 7 or an 8, both ways of getting that sum with 2 digits (26/35, 25/34) use up the 2 and the 3 - so r6c7 is actually seen by a 23 pair, which forces it to be 4. I'd like to imagine that was the intended solve path, because man its just so elegant!

34:58 for me after getting muddled with some early logic! Incredible puzzle :D

Nice puzzle! I notice how every puzzle you solve these days seems to have a 3 in the corner.. I'd love to see a statistical analysis of all the sudoku in the world to see if this channel is having a significant effect on how they are produced ^_^

48 minutes for me. Much more than easier than the wrogn puzzle I tried to solve yesterday.

My living room is such a mess now My mind is everywhere 🤯

In case someone is wondering about the name; ICHTUES splits to "Ich tu(e) es", which translates to "I do it."

Ok, this one broke my brain.

Once you deduct the top row is an 8, then you can continue with that thought. Two different pairs mean the 234 sees both a 2/6 and a 3/5. Forcing a 4 there, and a 5 next to it. Then the minimum in the sandwich clue to the left is 8 and that doesn't work. Eliminating that & forcing a 1.

Well, I spent 90 mins before realizing I’d misread the rules as ‘number of digits’ rather than ‘sum of digits’ 😂😢

Hey Simon, great solve as always. Fun fact: the puzzle and setter name is german: „Klappstuhl“ means „folding chair“ and ICHTUES is probably meant to be „ich tu es“ meaning „i do it“

@_inabox

8 ай бұрын

ichtutues is being cryptic here beacuse klapsztul is literally a sandwich.2 pieces of bread klapped together is i believe the folk etymology

I think I am very gradually getting the hang of these puzzles, as over the last couple of months I have increased the playback speed to 1.25x and now to 1.5x....

This was such a frustrating solve to follow along, because Simon often gets off on a tangent and forgets the rules 😅 The sandwich in row 6 was sitting there for around 20 minutes able to be resolved, but alas, we got there in the end

The opening is much easier than Simon made it I think? To make the total nine with 234 in box five or six would force a nine in the sandwich total for row 5 / column 8, forcing a repeated nine in the row or column.

I definitely feel like my solve involved a fair heft of luck and deductions that weren't properly substantiated. Just as well really, I think if I _had_ realised how many shortcuts I was taking, I wouldn't have had the patience, energy or brain power to work through the actual correct solve path 😂

Simon often reminds me of Master Po (Keye Luke) in the 70s Kung Fu series. Superbly able but as blind as a bat. 😋. I guess it's his aversion to Sudoku. Please don't change Simon.

you could write digits wherever you wanted if you had Epic Pen or something like it

51:33 for me. Magnificent puzzle!

Kick butt tomorrow, guys!

"7 and 8 aren't the same number... Isn't it weird?.."

I did have a go at this, but other than discovering at least one way of putting 1's and 9's in all the sandwich columns by pure guesswork I knew I wasn't going to make it. Good grief, I was staring at the 9 you put in the straight arrow box to the left and then wondering why that hadn't have to be the same for the one at the top. Since it was the same kind of construct in my opinion. Why could that not have been the one to span 234 and then the one at the left didn't. Hopefully more luck next time, but this was my 3rd attempt, no charms here...

I got the break in but got stuck in the middle. Eventually I chipped away at it & finished it, after several days.

"If we do that, then, THIS DIGIT CANNOT BE." I love SImon. "4 plus a number equals 9. Hopefully sudoku will give me the solution."

Did logic for columns 3/4/5 but didn’t continue to check effects on columns 7/8/9 which are the very same logic. Deleted test numbers too early.

Still couldn't figure out why the puzzle is named "folding chair". Feels like i missed out some hidden symmetry.

the 4 in box 6 sitting there for long time since you have deduced the 23 56 pair in box 3 and 6 are different and so it can only be 4

Simon shows that with row 5, the central box cannot be without a 19. (You'd either have a 1-cell sandwich, repeating the sandwich clue, or a 3-cell sandwich where the 9-crust is in the wrong place.) Then, one option for the layout forces column 8 to be without a 19 in box 8. It's the exact same situation, so it doesn't work, just as with row 5. Edit: Even crazier, Simon does disprove it, of course, but not using his previous logic of the repeated 9, but coming up with something else altogether. :)

@RichSmith77

8 ай бұрын

He only showed, initially, that row 5 didn't have a 1 or 9 under his second hypothesis, that there was *no* sandwich spanning the central box. He still believed it was possible for a three cell sandwich spanning box 5 to be in row 5.

@johnh2052

8 ай бұрын

@@RichSmith77 At 25:52, Simon explicitly says he cannot have a 3-cell sandwich spanning box 5 in row 5 because of the 9 conflict. This is before the deep analysis of column 8.

@RichSmith77

8 ай бұрын

@@johnh2052 For some reason I assumed you were talking about 24:15, when he first disproved a three-cell span across box 6, down column 8. At that point he hadn't yet disproved it by looking at the rows. As you say, he only does it for the rows at 25:52, which is later.

It was amazing and clever. I have seen two or 3 shortcuts, but such active viewing is the 🍒 on the top of this 🍰

How'd he know there wasn't a 9-1 sandwich in box 4?

Which is more common: sudoku with 5 in the center or 3 in a corner?

44:42 for me. I don't know but it seems the App runs VERY slow for the past few weeks...

(Anyone mention the following?-- It would have been nice to be able to write the #s in the circles outside the grid. Doing so would have lessened part of this mind bending going on with this puzzle.)

Wow.....