New Sudoku Technique Discovered

** Today's Sudoku**
We continue the series of extraordinary classic sudokus that exhibit brand new techniques that computer solvers do not yet understand. Today's puzzle is called Fancy Vase and it's by Qinlux. It contains a very beautiful trick - can you find it? Play the puzzle at the link below:
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Hi! We're Simon Anthony and Mark Goodliffe, two of the UK's most enthusiastic puzzle solvers. We have both represented the UK at the World Sudoku Championships and the World Puzzle Championships.
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Simon and Mark

[@qinlux-sudoku5778]

Beautiful solve Simon!! That was indeed the technique that I put in there, you found it and explained it very well. Thank you so much for covering this on the channel and I'll be looking forward to more classic sudokus from here :)

[@mostman]

Really neat setting there. Well done.

[@seanm3189]

I failed to solve it

[@KevinJayhawk]

I still don't really follow the logic. I mean, I can see it working, but there's no way I'm coming to that on my own

[@teambellavsteamalice]

@@KevinJayhawk The other way of looking at it is finding that the 3 and 8 each only had two spots, one the bottom left corner. IF neither went here, both would get next to the 19 center and either two 1s or two 9s would be looking at the top right corner. Then this number would have nowhere to go. So that forces the 19 into the three with 3 or 8, force the other 8 or 3 into the corner and you get the 6.

[@diersteinjulien6773]

"Normal Sudoku rules apply" is the most scary rule description there is.

[@AlonAltman]

Simon: We've done all the threes. Also Simon immediately after: There's a 3 and a 4 in this column. Never change, Simon! We love you videos!!

[@Mac_Omegaly]

25:29 for the time stamp! It's honestly fine to make mistakes as long as they are not destroying the logic of the puzzle. Lol I spoiled this from your comment.

[@TheSudsy]

also the six in the box 8. Must have been 7 minutes of me screaming Simon six bottom middle, bottom middle 6 Simon

[@tonn333]

Why do you wish he never changes?

[@brois841]

@@tonn333 because it proves he's a human, like the rest of us

[@kobe11111]

"...the computer does it by a whole series of nonsenses..." Simon vs Computer is always a good laugh

[@joshualangowells6101]

25:30 - "We have done our 3s!" 25:48 - places the last 3 :)

[@Gonzalo_Garcia_]

5:29 for me. A year and a half ago I wouldn’t even have thought of being able to solve this. Today I found it incredibly easy. The work Simon does teaching sudoku is absolutely stunning, I don’t thank you guys enough for that.

[@jurgenlandrie1380]

I couldn't agree more! Although in this one I find that Simon makes it extra hard on himself. I was able to solve this quite fast by following the trail of all matching pairs.

[@Crutypus]

15:46 for me !! As a mediocre sudoku solver with little experience in hard standard sudokus, I'm loving these "tricks exhibit" puzzles that let us think about this difficult tricks without having to be a god at scanning!!

[@andrewshelley410]

Bit unfair on the computer, it did the empty rectangle tricks with 1's, then with 9's, that gave it the '6'. Exactly the same as the human. Of course it waffled about a bit before it noticed it but come on, so did Simon.

[@chris5619]

I agree. It's just going through the order it's programmed to. It found the exact same thing. It just happens to be the only real way to get the next number after the initial 4 in box 5.

[@LouisBarjon]

human needs to feel superior to computer otherwise they lose hope..... But you just need to accept it, computers are way better than human, especially for something as easy as sudoku for a computer. A computer could solve a 99x99 sudoku with number from 1 to 99 in a matter of seconds when a human will need probably 10 years of solving it

[@Wjanabdjd138]

@@LouisBarjon Though the computer was legitimately incapable of solving shye’s puzzle from a couple weeks ago (at least other than just by brute forcing it)

[@LouisBarjon]

@@Wjanabdjd138 yes. Brute force works fine for a computer.

[@essentialatom]

I find him weirdly dismissive of the computer's "guessing". I mean, the chain it finds at 26:58 is perfectly reasonable and he would have seen that if he'd bothered to actually pause and look at it. Yes, it's bit bifurcationy - assuming that R1C1 is a 6 and following the logic around until the contradiction appears - but it's not just "guessing" and it's certainly not "bonkers" or "not a human move" as Simon says. You'd think he'd give it at least a glance, but no, he just likes his confirmation that the computer doesn't do geometry that well. EVEN THOUGH at 28:07, when it gets round to the 1/9 stuff he wanted to see, what it finds is not a million miles away from what he found - it's just rather more mechanical. And he just dismisses it as "a series of nonsenses". I mean really.

[@AdventCloudStrife]

The lack of a six pencil mark in r4c8 was giving me anxiety for most of the solve XD

[@TheBT]

That and column 6 row 9 which made me cry

[@annokrat]

got lucky with this one, just above 14 min! For some reason, my eyes got immediatelly drawn to box 3 and the empty rectangle. Probably because this advanced technique was the very first I ever learned from watching this amazing channel.

[@alanclarke4646]

I don't see it...

[@andyparkerson]

The easier way to see it, without talking about all the "dominoes" interacting, is to imagine what would happen if r7c3 were a 1 (or 9). Then both r1c2 and r8c9 would be 1 (or 9) and there would be no place in box 3 for a 1 (or 9). Great fun!

[@Socialdogma]

This is my break in too.

[@teambellavsteamalice]

Yeah, same.

[@Machine1136]

Alternating inference chains are not "guesses". They are almost the same as the logic you often use - "if this (strong pair), then this (weak link), then this (strong link) etc." until you spot a strong-strong contradiction.

[@Wjanabdjd138]

feels bad tho

[@jimjimellell]

Exactly! Computers cannot guess. Even "Bowman's Bingo" is not guessing. Simon likes to bash some types of logic that are not as "Elegant" as his method. I posted a similar comment last week that has somehow disappeared.

[@pauljohnpope]

I dont know why i started watching sudoku videos but ive watched many hour long videos and lots others. Youre brain is brilliant! 👏!

[@pokinDave]

I nominate the CTC children's book title - A Whole Series of Nonsenses.

[@longwaytotipperary]

Happy birthday Kimberly and Simon's sister!! 🎂

[@jacksontejada]

20:10! First time I've ever been faster than Simon or Mark. And I couldn't have done it without the tutelage of these two amazing individuals!

[@jorlove]

I had the strangest solve of this. I spotted the empty rectangle logic and had the 6 in r7c3 within 2 minutes, and then I stared at the grid for 10 minutes before noticing that there was only one place 3 could go in box 2.

[@JaggerG]

Scanning had been hard in this one, thanks to all the early pencil marking, probably.

[@Wjanabdjd138]

Exact same here haha

[@eternalblasphemy6526]

I've found a nice logic regarding 1s in box 7 (1 can go neither in r7c3 nor in r9c1, as it forces c2 to not contain any 1s). Had I found earlier that the similar logic would've been applicable for the 9s i nthe same box, I would've solved it in no time.

[@ariondys]

the entire puzzle crumbles after entering that 6 if you pencil marked

[@jakobr_]

20:33 was my time! c2 and r8 caught my attention immediately: “This looks like something Simon would notice!” So of course I looked into it and, sure enough, beautiful logic (boxes 3 and 7 in particular) and a straightforward solve followed!

[@Compliance0]

I tried and could not figure this out. The moment you pointed out the trick, I paused the video and was able to solve it in a matter of moments. I love how well you point out and explain these.

[@inspiringsand123]

Let's Get Cracking: 02:31 Puzzle Solved: 26:16 Simon's time: 23m45s And how about this video's Simarkisms?! Good Grief: 5x (02:59, 04:35, 14:08, 16:16, 22:29) Hang On: 5x (08:01, 14:12, 18:28, 18:33, 18:47) Beautiful: 4x (14:06, 17:30, 17:53, 28:17) Nonsense: 3x (23:28, 27:34, 28:23) The Answer is: 2x (15:27, 25:31) Clever: 2x (17:54, 23:05) Brilliant: 2x (26:19, 28:30) Wow: 2x (11:34, 21:45) Useless: 1x (16:24) Naked Single: 1x (24:13) Out of Nowhere: 1x (18:05) Stuck: 1x (09:18) By Sudoku: 1x (17:22) Bonkers: 1x (27:09) Approachable: 1x (02:50) Of All Things: 1x (17:22) Magnificent: 1x (01:31) Disappointing: 1x (15:58) We Can Do Better Than That: 1x (04:11) Wrogn: 1x (05:48) Progress: 1x (20:17) Plonk: 1x (16:25) Most popular digit, number(>9) and colour this video: One (80 mentions) Twenty Two (2 mentions) Orange, Yellow (2 mentions) 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!

[@vincentweaver6038]

Is "plonk" a new one?

[@psiphiorg]

"A whole series of nonsenses" is such a beautiful phrase!

[@h0016911]

Beautiful solve My only comment: Alternate Inference Chain (AIC) is not guessing. It’s a beautiful method based on logic. The best channel that teaches AIC is Sudoku Swami and I’m always grateful for his teaching.

[@davidbrown3257]

The three in bottom right!!!!!!

[@jaredmeier15]

8:52 Watching Simon mess up is such a bad feeling. This part made me want to scream "NOT '3', '4', or '9', SWITCH IT TO '3', '6', or '9' SIMOOONNN!!" It's all good though, you can't be a perfect solver at everything when you're already so good at seeing all the possibilities in milliseconds. Especially trying to make an engaging KZbin video while commentating. Keep it up Simon! Love your videos, even one and a half years later.

[@TheKirbyness]

Wow that's actually incredible, looking at the original grid it just looks like there's nothing you can do at all but if you see the 19 trick in box 3 the entire puzzle literally crumbles instantly

[@alanclarke4646]

What 19 trick?

[@andrewjfarrington]

Placement of a 1 (or 9) in either corner of box 7 forces an identical digit into the top of column 2 and the end of row 8. Both these cells eliminate all the available real estate for this digit in box 3. The empty rectangle in your comment below is just this logic in reverse!

[@jacksontejada]

I actually found a different break-in. With c2 and r8, I managed to determine that r9c1 could only be 3 or 8, which gave me a quadruple and gave me the 6 in box 7.

[@Wecoc1]

I believe what Simon found on 14:21 are two identical Grouped Discontinuous Nice Loops, one affects 1s and the other affects 9s.

[@tessabrisac7423]

Very Nice Loops, though I don’t quite understand the notion of a “discontinuous loop”. Is it too much to ask you to show how this works?

[@Wecoc1]

​@@tessabrisac7423 It's a bit hard to make it clear because he explained the loop backwards, it would be more sensible to start from r9c1 (or, as he later noticed, it's more useful on r7c3). Because of the reasons he explained, 19 can't be in those starting cells since it's forced in that bent yellow part. If, as in this case, the loop closes with a contradiction (you can eliminate 19 on the starting cells), then it's called "discontinuous".

[@condor1234]

Your explanation is brillant!

[@naphackDT]

First time being faster than Simon's video... 16:30 minutes, got the logic after 2 minutes, got stuck because I missed a naked single for 5 minutes and was just frantically scanning the grid like crazy.

[@kevinmartin7760]

from 22:15 onward, an 8 is forced into R1C2 by Sudoku rules (8's in R2C8 and R3C5 and R4C3) and the 5 already in R1C1.

[@RoderickEtheria]

Alternative Inferrence Chains are not inherently guessing, at least not always.

[@thealienontheinternet]

Last time I was this early, Maverick hadn't flown past my window yet

[@jem5636]

Oh man, I always love these videos so much! These are one of the most calming highlights of my days. Love this channel!

[@theunwelcome]

Simon! While I was watching this video, my mail came, and in it was: my book! And it's every bit as beautiful as you've purported it to be, can't put to words how glad I am to have backed the project.

[@namelessminionveinreaver3763]

The proper pronunciation is based on the cost/value. Under $20 USD it's the hard A sound as in Vayce. More than that it's a Vozz. Otherwise you may distinguish the two by the fact that one is meant to support/display the flowers inside, and the other is decorative on its own.

[@miaash3870]

You are brilliant at this game! My first time here with you!

[@DeborahJLeslie]

Oh Simon. Americans don't say vaze (to rhyme with haze), but vase (to rhyme with case). In any case 🙃, I love that we still spell it 'rhyme'

[@ragnkja]

I didn’t notice any voiced “s” in Simon’s pronunciation, but I’m Norwegian so I’m probably not the right person to ask.

[@bobh6728]

I have a new secret that will help Simon solve these puzzles. there are 9 3’s in a properly solved sudoku. He asked how many 3’s do we have and upon seeing 8 of them, he says all of them!!

[@frozenBlueSky]

If you turn the Board about 45 degrees counter clockwise and add a bit of fantasy the given numbers forms a vase. With a single Flower on top. And with the solving, every Solution seems to grow out of its root. With the 3 and 5 in col 5 the new solution grow to a 2. blossom. And with the 6 in column 8 the main blossom is growing further and gets an additional leaf. In fact this main blossom in rect 3 keeps growing until the puzzle is solved completly. Didn't expect such a beauty in something like a sudoku. Its like a poem, absolute fantastic. Thanks for sharing.

[@LithmusEarth]

5 minutes in, there are only two spots for 3 in box 7. one of which you marked with the 139 penciling.

[@hobbyist518]

The first "new technique" sudoku I solved on my own. When you were doing your intro, the orientation of rows pointing at the bottom left square, which then points nines and ones at the top right, was just screaming at me. Paused the video, gave it a try, and made it to the end.

[@SpongeJ]

I was thrown off by Simon's note of 349 in r4c8 and thought there was an Xwing on 6 in column 4 and 8 ( which would give the 6 box 7 and start the puzzle off). I was so proud of myself for spotting it. Hélas I was mistaken.

[@ekdar123]

17:21 for this one. noticed the trick in B7 right away and then struggled with the traditional sudoku part.

[@shivanshukashyap7476]

This solve was extremely difficult, Thanks for sharing it and the best thing that I love about you solving classic sudoku sir is that you solve by puzzles on the basis of pure logic and not try to spot all those different techniques like skyscraper and all which are very hard to spot anyway. ❤🙏

[@57thorns]

9:14 is a mistake. There can be a 6 in r4c8. I hope this does not taint the solve. (I suppose not given that it would be all over the comments if that was the case.) Always double check if you fill in all candidates and leave out a corner mark.

[@liz257]

I only just learnt the rules of basic sudoku this week I had gone all my life without ever solving a single sudoku problem. I want to improve my technique :)

[@ClintWebb]

Weirdly, the 6 in box 7 is how I broke into the puzzle. I found this because I noticed that box 7 was restricted with 1 and 9. if a 9 or 1 was in r9c1, then the same number had to go in r1c2 and r8c9, meaning there was no place for that number in box 3. at that point I filled in all the available options in box7, and then knowing that 1 and 9 had only 3 places to go in, I could eliminate it from r7c3, therefore I placed the 6. because of that 6, I could then see only 1 place for 6 in c4, and then just sort of followed the trail (although it did take me a while to notice the 3 in box 2, I was stuck for a bit there). Once a cell caught my attention, I simply entered in all the available options, and quickly found the path of which cells were limited. A really good puzzle, and I had a great time solving it. Thankyou.

[@CMLachky]

Great Puzzle!! I was SO CLOSE to getting this one! I realized that it had to do with 1's and 9's in box 7, but couldn't quite figure it out until Simon had just started talking about it. Very cool logic!!

[@alexandradavison3908]

I got the 4 at the start 🙏🏻

[@eduardos4607]

I managed to solve this without any help. I'm getting much better at puzzles. I'm really glad I found your channel

[@NotElusivePanda]

It took me almost two hours fun to see you breeze through it.

[@blandingswest6560]

A ton of beauty here! One can actually solve (7,3) AS THE VERY FIRST MOVE by noting that the 1's and 9's are restricted to (7,2), (8,2), and (8,3) in block 7. And once that is done, the entire rest of the puzzle collapses through a cascading series of naked singles.

[@mattbendzinski4945]

I would NEVER has caught that trick....I would have gotten about a 3rd of the way and given up. WAY beyond my abilities, but I do love when you get these....super cool !!!

[@jacobcapra09]

Pleased to have actually solved one of these strange classic sudokus. Once I removed a few possibilities from box 7 by noticing it’s relationship with box 3, it became classic sudoku for me with a bit of extra brainpower required here and there. Great setting, and quite approachable if you’ve watched a few of these classic videos but a beast if you haven’t!

[@elaadt]

Beautiful puzzle. Simon, you should have coloured the vase, if only to show some appreciation to the effort put in to creating it.

[@ronladhatter]

I agree that with this kind of sudoku where there is a trick to find to crack the puzzle letting it flow pretty easily following that is a nice reward that puts the focus less on continuing to be difficult and more on that one initial break in.

[@cluso9985]

Fantastic puzzle. Needed Simon’s help to find the trick, then able to finish on my own :)

[@billyoung8118]

Once you figured out the 1-9 trick in box 3, the puzzle sort of solved itself. And by "you" I do not mean "me". I never would have found that. Well done, Simon!

[@grenvillephillips6998]

Simon's attitude to the computer solver reminds me of MacReady's response to the chess computer in the movie The Thing (1982)

[@ashleylordess5621]

I would never have spotted that trick. Nicely done!

[@longwaytotipperary]

Wow! The solution is amazing!! 😲

[@th.nd.r]

Incredible setting from Qinlux and wonderful solving from Simon! Love these human vs. machine battles.

[@kurzackd]

Has 30 given digits. Takes 16 (SIXTEEN) minutes to get the FIRST digit. Takes only 8 more minutes to find ALL the remaining digits. Wow! That's some genius sudoku right there! :O

[@jamesking9807]

He placed the first digit, a 4, 25 seconds after starting the puzzle.

[@kurzackd]

@@jamesking9807 I don't count this one because it was a "given", i.e. it was immediately obvious that it should be placed. Technically, the puzzle has 29 given starting digits, but in practice they're 30.

[@vincentdesiderio767]

Cracked it the same as you Simon..Great minds think alike !! Thanks.. Keep it going!

[@georgeaman1938]

First time I found the trick in a classic difficult sudoku. It was a nice puzzle!

[@palacerevolution2000]

It took me a hard 25 minutes (w a restart); applying lessons I have learned here. I ended up with the same key boxes, but I couldn't have xplained it the way Simon does. Thank you guys.

[@dr4gondude339]

This was fun to solve. It took me a while to figure out the technique, I decided I needed a cup of tea and noticed it as I was getting up.

[@amp2amp800]

Nice Simon. First time I've done one without your help. I looked at the options for sixes in the phistomafel ring and boxes to determine and place exactly one 6 in the ring at r7c3, and then deduced a virtual 19 pair along with an 8 or 3 in box7 with making a virtual 38 pair with the corner. Thereafter it fell apart... but it took 5 goes before I did it accurately!

[@ianpearse4480]

Wow, that was cool. Thank you for the lesson. Love the exclusion thing. I was able to fill it in after the 19 EXAMPLE. Very nice.

[@AussieJohnny]

Like Simon I have also watched too much chess on the internet. I sat up until about 2:30am (Brisbane time) waiting for Magnus to finish off Ian's challenge in Dubai....which he finally did and my sleeping pattern can revert to something more sensible.

[@Coyotek4]

18:16 ... I think I did well spotting the trick, but my scanning skills were a bit suspect to say the least. Nice classic!

[@TurquoizeGoldscraper]

11:30 for me - I got drawn to the mostly full C2 and R8 and then saw how those affect B3. Pretty quick solve after that's out of the way.

[@Cyclone001c]

I thought of the break in trick from the other way. Placing a 1 or 9 into r7c3 or r9c1, forces that digit into both the endpoints of the c2/r8 lines (only place for the digit in the column/row), thus eliminating all candidates of that digit from box3.

[@VeritasUnae]

Really interesting puzzle! Simon found the break-in beautifully.

[@vladhatter]

Absolutely genius. I couldn't for the life of me see where the logic break was, I couldn't agree more about loving puzzles where once you find the break, the puzzle seems to fall apart 😁

[@TheNewAccount2008]

Great puzzle, but I would never have spotted that...

[@bristolrovers27]

First oooh !!!! I'll settle for 36 minutes, very pleased and didn't find it over difficult

[@thomasmairowski9101]

16:45 Can someone explain why in the field with the "6" can not be a 1 or 9? In the field are 3 digits: 1,6,9 An de also said that it can be 1,6,9 but then he excludes 1 and 9. Why?

[@wanderlustwarrior]

22:54 for me, and I'm happy with that time! A nice symmetry on the puzzle.

[@JCGodartSudoku]

FWIW, JSudoku will spot the pattern very soon as a grouped turbo fish (similar to empty rectangles, but linking two empty rectangles) : "R5C4 = 4 (hidden single in N5) Two String Kite in R9 & C4: (6): R9C1=R9C5-R7C4=R1C4 -> R1C1 6 Grouped Turbot Chain (1): R8C23=R8C9-R2C9=R2C13-R1C2=R78C2 -> R7C3, R9C1 1 Grouped Turbot Chain (9): R8C23=R8C9-R3C9=R3C13-R1C2=R78C2 -> R7C3, R9C1 9 R7C3 = 6" The rest are singles

[@ziziorens348]

I've spent an hour and a half bashing my head against that blasted box seven never realising that r7c3 can't be anything BUT 6.

[@DanielSloane]

This is the first of these tricky classics that I've managed to solve. My time was 13:50. Once I saw the trick, everything fell into place.

[@fubaralakbar6800]

After the naked 4, the next digit I got was a 3 in r8c3, by following a chain from r7c3 to r9c1. Basically, I already knew that r7c36 would result in r9c1=6 because they are conjugate pair. So the question was, what would r7c3=6 do? The chain revealed that it would yield r9c1=8, therefore this cell is a bi-value of 68, eliminating the possible 3, which was also part of a conjugate pair, therefore r8c3=3. That alone didn't help much, but it did it's own small part. I later discovered the 6 in row 7 by contradiction--something I'm not terribly comfortable with, but if the only alternative is more headaches, then I do it. I recommend starting at a cell were three conjugate pairs meet. These cells can be extremely powerful, and appear in pretty much every sudoku. You can chain your way out of them, or into them, usually solving one of the pairs, and sometimes all three : )

[@gibbeldon]

Lol, I didn't see that 6 was a naked single. I deduced that the other possible cell for the 6 (R9C1) couldn't be a 6, because one of the far out cells had to be either a 1 or a 9 whilst the other wasn't. Which in turn forced either a 3 OR an 8 in the three cells in the middle of box 7. But since cell R7C3 in the upper corner of that box could be neither of those, the other one had to go in R9C1 turning it into a 3/8 cell, excluding 6 from that position. Now 6 had only one cell left in box 7 and the puzzle was cracked. Seeing that naked single would have saved me some :D

[@joelstevens5670]

I’m actually starting to run out of superlatives with these puzzles. That latest idea was nothing short of ridiculous; it was that obvious once you saw it and yet it was not easy to find but then when you did find it the whole puzzle just collapsed from a seemingly impossible position. It’s logic so good it’s almost logic defying!! Genius.

[@neiljerzynek5001]

I spotted that 2nd time

[@Handel9000]

16:25 Plonkins™ ! 😃

[@opsports50]

Loved the puzzle. Managed to beat him for the first time today. My incessant need to turn everything into a coloring puzzle finally pays off.

[@stegra5960]

Yey. I did it in 24 mins. First of these 'new tricks' puzzles I've been able to do and first time I've been close to Simon's time. I spotted that a 1 or 9 in r9c1 or r7c3 would have to be repeated in r8c9 and again in r1 of box 3 thus eliminating itself from c2 altogether. Same logic, just a different way of looking at it.

[@G.Aaron.Fisher]

9:50 Had the 6 in R3C7 within 60 seconds, and was kind of slow cleaning up. Didn't really think this piece of logic was owing its own video.

[@guyb7005]

this was brilliantly executed. Love to hear you think logically!

[@Bur6212]

14:25, that’s called an “8” 😉

[@MadMetalMacho]

Hey Simon! I don't know what you do when you remove pencilmarked digits (the top left kind) but it sounds like you press several buttons every time. You can just hold shift to pencilmark/unmark those, even if the app is in a different mode. Smooth as butter.

[@or3213]

I sort of figured out that the 6 goes in r7c3, and the puzzle quickly solved from there in 11:20. But I don't really know how I got there... I'm watching Simon just to know what the trick in this puzzle is even supposed to be.

[@TJB147]

Love these videos. Especially seeing how world class solvers go about the puzzle when the going gets tough

[@michaelhoffman2011]

Took me 23 minutes. Honestly i think i found the "trick" very quickly. in box 7 there is only 2 places where 3,6 and 8 can go. Since we knew that the "yellow" digits had to contains 1 & 9... 6 was very very easy to play and then the whole puzzle almost solved it self. very clever puzzle

[@bluerizlagirl]

That was a beautiful explanation of the reason why you insist on solving puzzles the way you do! As far as the computer solving goes, I'm sure someone will eventually find a general technique that covers a lot of these cases at once .....

[@genoh9632]

it was fascinating to watch you place about 20 first big numbers the exact same way I did, although it took me 9 times longer.

[@nateallen8909]

Now that the WCC is over it's less of an interesting question, but I'm curious what channel(s) you watched for the chess match! I find it very interesting to see what youtube content is enjoyed by which other youtube creators... Thanks for the entertainment, as always :)

[@gombospatrik]

I did it in 20 mins, which would mean I was faster than Simon.xDDD But that's not the case, regarding I didn't need to explain this puzzle to anyone, plus knowing the video's title was 'new sudoku technique discovered', I didn't take that much time pencilmarking around, looking for X wings and common things like that, which took nearly half of Simon's video. Still a great feeling of success, I never managed to do any classic sudoku Simon solved, cuz they're usually extremely tricky.xD Thanks for the video, it was absolutely great to watch.

[@Raven-Creations]

Interesting puzzle. I was suspicious of the empty rectangle from the start, and the geometry hinted that the key was in box 7. I do like it when setters drop hints like that. After placing the 6 in box 7, I went through it like a dose of salts, whereas you seemed to have to sweat it out, but I couldn't see what you were missing. I did have some pencil-marks that you'd missed, and these were helpful (e.g. when placing one digit takes a pencil-mark of another, etc.), so that might have explained the difference.

[@coyote4237]

Thank you.

[@ragnkja]

Finally, Simon asks “can we reuse this logic somehow?” And it’s not one of the many situations where it would have been useful :(