The Lennon and McCartney Of Sudoku

** PATREON UPDATE **
Remember you just have until the end of today to submit a solution to Philip Newman's "Palpatine's Design' - the hardest classic sudoku ever.
Also Simon's solve of Phistomefel's latest puzzle: Slitherlink Liars - which is a 100 minute video (!) will be uploaded tomorrow!
** TODAY'S PUZZLE **
This is a very special puzzle that's the brainchild of two wonderful setters. Abed Hawila and Mr.Menace have combined their considerable talents to construct a sudoku so brilliant that another top-notch constructor described it as possible the best puzzle they've ever solved.
Play The Butterfly Effect at the link below:
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Rules:
Normal sudoku rules apply. For each line, digits on the line have an equal sum N within each 3x3 box it passes through. If a line passes through the same box more than once, each individual segment of such a line within that box sums to N separately. eg R1c4+r2c4+r3c4+r3c5 = r4c5+r4c6 = r3c6+r3c5+r2c5.
▶ NEW PATREON CONTENT ◀
We have a new Competition running involving the world's hardest classic sudoku. It's been discovered by Philip Newman and, if you can solve it, send us your answer AND how you figured it out by 31 March. Philip will pick the best solutions, which will win a prize.
Simon's attempt to solve The Sudokutown Murders is out now.
We have released a new crossword video featuring Mark's attempt at the a Friday New York Times crossword, Matt Gaffney's meta crossword and the Listener crossword (which was a numerical).
We've also just released March's reward, a sudoku hunt called Guess Again. Send in your solution by 20 March for a chance to win a prize.
Also new on Patreon is Simon's solve of Sam Cappleman-Lynes' Tie Fighter Starbattle.
Other Patreon exclusives:
- Simon's solve of Balance = Entropy, a brilliant new sudoku from JeremyDover and Raumplaner.
- Mark's latest fight with The Times Club Monthly Special cryptic crossword.
- The QAS ("Quite Approachable Sudoku") Hunt (solutions due tomorrow please!)
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[@kaymennens9956]

What a humbling comparison! Thanks for the solve, neat and grasping all the intended logic, as always! -Mr.Menace

[@sampathkumar-ej7xl]

Hearing simon say the puzzle with simple rules is recommended by people like Zetamath started solving it. After battling my way to the end saw the names of the constructors Abed Hawila and Mr. Menace and thought no wonder. Just fortunate to get to spend time solving some great puzzles. Thanks people!

[@BozoTheBear]

I LOVED this puzzle, thanks to you and Abed! So happy to have found all the logic, even if it took a bit longer than Simon.

[@iain_nakada]

Agreed, fantastic puzzle Mr Menace! Perfect level of difficulty for me, and I love good use of symmetry. Spotted line 7 as important very first thing, then promptly forgot about it among all the 15s and 17s everywhere... XD

[@M_Northstar]

To me, the most impressive thing about this puzzle was realizing that the symmetry actually was a red herring! Any experienced solver would see that symmetry, and immediately look for a break in it. Seeing the two 2+1 lines in the lower right corner you'd conclude, just as Simon did, that they were there to disambiguate some late game knot, and be distracted away from realizing that the small asymmetry just so happens to populate almost the entirety of the seventh row with lines that can yield logical deductions.

[@sarahgray1735]

This made me feel better! I was kicking myself for ignoring the seventh row for far too long, but maybe its because I’ve become an “experienced solver”! ;)

[@shellmichael9665]

I love that Simon now has to pause when he says “There’s no such thing as a Schrödinger cell in sudoku”. All it takes is one brilliant puzzle to flip Simon’s perspective forever.

[@sandpiperbf9767]

It's wild how Simon can wake up everyday, and always be faced with a new baffling puzzle that he is fully capable of solving but still presents the challenge. Honestly, the dream! And I am grateful that that dream can be shared with all of us. I hope someday I can solve these as they come, but still struggle with anything that takes Mark or Simon more than 20-30 mins

[@HunterJE]

13:00 Ahh that universal solving moment when you think you've found a big breakthrough and realize you've just landed on result you previously proved from a different direction...

[@inspiringsand123]

Rules: 04:12 Let's Get Cracking: 05:37 Simon's time: 39m46s Puzzle Solved: 45:23 What about this video's Top Tier Simarkisms?! The Secret: 5x (10:38, 10:38, 10:47, 10:52, 10:56) Schrödinger Cell: 3x (19:41, 20:22, 32:17) Phistomefel: 1x (02:42) You Rotten Thing: 1x (13:10) And how about this video's Simarkisms?! Ah: 17x (07:21, 13:06, 14:05, 14:05, 18:57, 24:02, 24:19, 25:28, 26:50, 31:36, 35:50, 38:16, 39:17, 40:03, 40:47, 42:33, 44:43) Hang On: 8x (05:22, 15:56, 30:07, 32:55, 33:41, 41:55, 41:55, 43:55) Clever: 6x (22:05, 22:22, 31:36, 33:20, 45:26, 45:29) By Sudoku: 6x (38:42, 39:07, 40:07, 41:01, 41:51, 42:41) Beautiful: 5x (19:06, 21:54, 21:56, 27:02, 38:21) Sorry: 4x (10:22, 13:25, 15:09, 30:07) Good Grief: 2x (31:16, 31:16) The Answer is: 2x (14:26, 30:26) Stuck: 2x (12:22, 35:44) Disconcerting: 2x (25:17, 43:53) Stunning: 2x (45:33, 45:33) Obviously: 2x (08:13, 11:00) Wow: 2x (45:24, 45:25) What Does This Mean?: 2x (33:35, 36:10) Pencil Mark/mark: 2x (31:00, 37:19) What on Earth: 1x (39:34) Goodness: 1x (33:46) Naked Single: 1x (43:01) Home Straight: 1x (43:44) Horrible Feeling: 1x (39:05) Brilliant: 1x (01:22) Ridiculous: 1x (35:37) Take a Bow: 1x (45:39) Our old Friend Sudoku: 1x (36:28) Famous Last Words: 1x (43:50) Flummoxed: 1x (25:56) Flurry of Activity: 1x (45:18) In Fact: 1x (14:37) We Can Do Better Than That: 1x (40:33) Progress: 1x (37:10) Unstuck: 1x (12:26) Most popular number(>9), digit and colour this video: Fifteen (32 mentions) Eight (81 mentions) Orange (13 mentions) Antithesis Battles: High (7) - Low (0) Odd (4) - Even (2) 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!

[@dedacraamati]

My time: 39:54 So close 😁

[@tessabrisac7423]

Bobbins! CtC will have to recycle mugs and t-shirts, “bobbins” is forgotten!

[@richy77]

Add like "meant to understand" or something to the Simarkisms list

[@Censeo]

All the six mentions of "by sudoku" are mentioned in a four minute span of the video

[@piarittersporn]

It took me twice as long as Simon but I thoroughly enjoyed this wonderful puzzle.

[@hrishikeshbakshi8961]

Sir, Take a bow for the lines you said on 29:37 !!!! 'Giving absolutely clear logical reason to audience and not just using uniqueness' is something you are focusing on! Salute to you!

[@b-you-tube]

Solved this in about 3 hours using almost identical methodology to Simon. This was the first puzzle featured on CTC (aside from GAS puzzles) that I've solved, so I'm super proud :). Thanks for the video

[@alaricschenck8051]

8:46 "This I suspect has been added later to disambiguate some pattern that occurs towards the end of the grid." - Then Simon proceeds to use it as the key to break into solving the puzzle.

[@fluscim]

Here comes the sun is Harrison. Checked just in case, but yes. Exactly zero digits here. Not even a triplet. :-/ What. A. Channel. The kindness is just... human-friendly. So thanks.

[@MattYDdraig]

38:57 Some magnificent logic especially in row 7. Thoroughly enjoyable and undeniably brilliant.

[@thesundancekid123]

Another kind comment for you to read, Simon! Always a pleasure to watch you solve and explain these gems.

[@andilee3537]

Massively pleased to have solved this one. Found it really hard, but made it without watching the video!

[@th.nd.r]

Beautifully set and solved. Row 7 is MVP

[@EmilyGamerGirl]

Yeah, as soon as you knew the bottom-left line added to 15, well, 15 is the triangular number for 5, so it had to be a 12345 quintuple. That's the easier way to see what's going on

[@lauracortes7720]

yess that was driving me nuts haha

[@richy77]

ohhh

[@olivier2553]

Simon is thinking at another level than us mere mortals, such trivialities are not for him :)

[@orosma868]

Triangular numbers are usually Simon's go to. I was getting very frustrated but actually enjoyed his alternative approach. He always sees things in a different way to the majority, which is why his solves are so beautiful.

[@msolec2000]

Just had to give this comment the 15th thumb up and the 5th reply.

[@zetamathdoespuzzles]

I'm so glad to see this here, well deserved, what a construction. I can't wait to watch Simon's solve. Mine will be posted on my channel sometime soon (-:

[@kwongshuchung]

Very impressive one Can't even put a digit in this puzzle But i feel i keep improving 🤓

[@cjktoo]

Right. I am officially stealing "It hasn't yet rolled over and let us tickle its tummy."

[@awilliams1701]

Based on the title I thought we were going to get some Simon's Guitar sessions. I always love those.

[@longwaytotipperary]

You had me at Lennon & McCartney! ❤ is all there is!

[@erickehr4475]

33:33 for me. A pleasingly symmetrical time for a nearly symmetrical puzzle. I had to use uniqueness at one point to make progress. I haven’t watched the video yet, but I imagine Simon will find some other route.

[@davidhughes7174]

A beautiful puzzle that put my logic skills to the test and I passed, somehow. I also enjoyed your solve Simon. Thanks to the setters, well done.

[@nicocost33]

I love this one! Thanks!

[@icepyrox]

I tried this but the video started in the background. I got most of the breaking before Simon, but realizing r7 was key took me longer. Once he mentioned it I saw it and was able to finish at 58:58. I used to comment on Simon not scanning, but either he has been getting his sleep lately and doing better or now that I'm attempting, I'm shown to be wrong. Several times he's like "and here is a naked single" on a digit I got late in the puzzle... truly master class solving

[@mritty115]

I really want to see video of Simon actually competing in one of these Speed Solving competitions he occasionally mentions. Just Simon against a clock (or other solvers) without the constraint of not using uniqueness or other techniques, and without the need to explain each step in his thought process. :-)

[@Gonzalo_Garcia_]

20:50 for me. What a great puzzle, probably the most elegant use of equal sum lines I’ve seen so far. Truly awesome.

[@BigAsciiHappyStar]

Today’s Sudoku-In-A-Song Imagine there’s Row Seven With all the equal sum lines No cell except this one Can have the number Nine Imagine all the people, watching Simon today

[@ericpraline1302]

This was indeed a wondrous puzzle with many delightful twists and turns. I took the scenic route.

[@bilbo206]

I’m waiting for the day Simon receives the puzzle with a Schrodinger cell.

[@leojs5673]

Prepared myself a nice bowl of cereal for watching today’s video 🤓

[@davidrattner9]

What was your cereal of choice?

[@leojs5673]

@@davidrattner9 good ol Froot Loops

[@davidrattner9]

@@leojs5673 love fruit loops..just got some myself!!.Excellent choice :-)

[@teruokun-us]

Got it in 24:14! It was quite fun and figuring out how the bottom right lines fit in after so much deduction at outset was really very satisfying

[@PathOfShrines]

Really cool puzzle. Took me quite awhile to find the logic in the bottom right, but then it came together. Very nice. 47:43

[@dakotaf248]

great puzzle... great solve. Thank you for your time!

[@andrewpalmer5189]

I found that one extremely hard. I got to where Simon was at 26:26 early enough, but ground to a halt at that point. Had to sneak a peek at the video after staring at the puzzle for an eternity. It was only when I saw the significance of where to place the high numbers in row 7 that things started to move. Excellent puzzle though. (PS: And with a Lennon/McCartney title, there was a chance missed to introduce the "45" fact with "Do You Want to Know a Secret"...)

[@danielrhymer1762]

18:56 for me! One of those which I just happened to spot and then it fell out nice and quickly

[@bezowee]

Lennon and McCartney in the title and no guitar intro?

[@CrackingTheCryptic]

I let you down and I let myself down. (And I ran out of time, sorry!!!) I will make up for it. Reply to this comment with your favourite Beatles intro... :)

[@longwaytotipperary]

@@CrackingTheCryptic Let it Be, Ticket to Ride, Shake it Up, Come Together, You can't Do that, And I love her (and about 30 others)

[@bezowee]

@@CrackingTheCryptic I really wanted to say don't let me down but ticket to ride is just fantastic

[@davidrattner9]

@@CrackingTheCryptic here comes the sun, let it be, all you need is love, twist and shout, blackbird, a little help from my friend..just to name a few..but whatever you choose will be magnificent

[@pouletbelette]

@@CrackingTheCryptic I think you should choose your own favourite intro. Can't wait...

[@57thorns]

I was looking a lot at line 7 there for a while, and Simon starts looking at it again at 31:24. But the really interesting part is that the line segment in box 7 adds to 15, it has to be 12345 placing the blue square in r8 and r9 of c1.

[@alexgrunde6682]

I used a different, more obtuse way of deducting the 7 in r7c7. I used set to determine that the digits in r7c1-4 are the same total as c7r1-5 and 9. Once you know orange totals 15, the max possible for r7c1-4 is 21, which is the triangular number for six digits and thus 6 can’t be in r7c7.

[@joannevroon3607]

Sometimes I have gutfeelings about some numbers, like 9 in c2r2 and 7's on the diagonal line... but I can never prove my own point, but Simon knows, he can explain my mind better I can! I also love how he has a logic-trail leading to the 9 in c2r2 and just takes a turn and doesn't put the 9 in for a long time... He sees logic I cannot even spot when searching for it.

[@MarushiaDark316]

Am I alone in thinking it'd be interesting if Simon and Mark were to try their hand at setting a puzzle and play each other's creation?

[@doublelxp]

There's a video somewhere of Simon solving a puzzle Mark set. I don't remember which one it is, but it was one they did around the time they released one of their apps.

[@MyriamTT]

Another brilliant puzzle. Thank you !

[@guitartailor]

Mark and Simon are the real Lennon and McCartney...

[@Raven-Creations]

Absolutely beautiful construction. Your deliberations about R7 would have been much quicker if you'd pencil-marked 12345 on the line in box 7. You knew it was 15, so why keep considering anything else? In R7, the 9 can only go in R7C4. There must be an 81 on one of the dominos, so you can't have 7 on the other, because it would need to go with 2 and create a second 9 in C7. Therefore the diagonal line is 7, with 62 and 81 domino. The 81 domino can't be in box 9, because the 62 domino in box 8 would push a second 8 into box 9. This was one of the most beautiful puzzles you've done, using only a single variant, almost symmetrical geometry, and lots of lovely logic. This variant is rapidly becoming my favourite. Every one has been a treat to solve, but I think this is the best yet.

[@nicolasmartin224]

a bit of a complicated explanation to tell that the 6789 have to have exactly one overlapping digit :) you can see that the yellow cell sees orange and blue. so they can't be different because of that and can't be the same because there is only one cell overlapping in box 1 :) so that means there is only 1 digit that is the same! (but you're still way better than us simon, we can't figure those complicated explanations)

[@bobbis.172]

When Simon whispered while saying "Don't tell Mark, but..." I leaned in closer to my phone to listen to the *secret*

[@unbekannter_Nutzer]

Sometimes you have to explain a habit of yours. You have worked out early, that the diagonal in box 5 has to be 12(3/4) and eliminated the 4 from the corner, because of col 9. Later you realize, the sum has to be 7 and the options can be reduced to 124, but doing that, you reintroduce the 4 in the cell. It didn't cost you any time, to eliminate the 4 a little later, but I'm wondering if you oversee such details on purpose, to make the audience go crazy. :)

[@Coyotek4]

22:35 ... I thought I fared rather well on this one. Nice puzzle!

[@timcotton1782]

With this puzzle, I began by realizing that the 9-digit lines which each have 2 digits in Box5 set the math. Because they each exist twice in the other involved boxes (2 and 4), the N value had to be 14 and 15, making the value of the 2 digits in those boxes on the 7-digit lines 17 and 15 respectively. This defines the "overlapping" digit which must be in R2C2 as 9, accompanied by 6 or 8 in each case, leaving 7 as the N value for the line from R3C3 to R7C7.

[@AndreAy1975]

Solved it with help from the video.

[@abj136]

I was having a great time solving the puzzle of R1C5+R1C6=R1C7+R2C7+R3C7=R3C7+R2C8+R2C9 and ditto on the bottom left. Turns out R1C5 and R1C6 had a range of 11-17 and numbers worked out to force R6C7+R8C7 is also 11-17. And ditto the pair of numbers on the left. It was so BEAUTIFUL. But then it all became clear. I had confused rules.

[@sebastienlecoq3956]

"45 is Odd" should be the new secret

[@charliemurphy1269]

I actually used complicated deductions from SET to solve this, on row 7 and column 7. Mind you, that's probably why it took me an incredibly long time 😅

[@Nickgerrits-vy2sp]

The last 10 minutes of solving took me 40 ish minutes alone

[@cmpedicini]

Maybe I'm getting better at spotting? At 9:51 I'd figured out R1C5 & R1C6 (or E1 & F1 in alternate notation) MUST be an 8-9 pair since the other 7 digits had to add to 28, leaving 17 for the sum of the other two digits and only one way to disambiguate.

[@thezanycat]

The other seven digits could add to 30 with a 6/9 or 7/8 pair in the top making 15.

[@RichSmith77]

"7 digits had to add to 28" *7 digits have to sum to at LEAST 28. As Daniel says, they can sum to more, including to 30.

[@kathyjohnson2043]

I would think that 'uniqueness' WOULD be a form of logic since it is seems to be a deductive inference.

[@doublelxp]

The problem a lot of people have with uniqueness is that it presumes a single solution rather than proving it. It's very possible to "solve" a puzzle by avoiding a deadly pattern but it doesn't inherently make the solution unique.

[@alienrenders]

24:13 is my time. Realizing that if you use 15, then the lines in box 3 and 7 are limited to the digits 1-5. This causes a lot of contradictions with certain digits. So the puzzle broke open right away. I think I missed some other logic as I just eliminated 15 from the pairs in box 2 and 4 where possible. Now to watch how Simon did it. edit: Nice solve. I kind of did it the other way around. I found the 7's on the ends of the line that goes through the center box diagonally within a couple minutes. Trying 9 and 8 break the puzzle and the 7 has nowhere else to go on row 7 after that. You can also try 6 and it breaks the puzzle, but takes a little more work to see.

[@emilywilliams3237]

Very much enjoyed this video. I have read all of the comments posted to this point, and note that some folks saw things that Simon didn't. *sigh* yes, I am sure that you did, but I also wonder whether Simon would have seen different things if he had been solving only for himself and not including commentary (and probably going through the rolodex of his mind for suitable poetry references or historic speech excerpts or the names and dates of Byzantine mathematicians should the occasion arise to mention them ...) Your mind, Simon, is fascinating. Thanks for another interesting video.

[@leickrobinson5186]

48 minutes for me! Pretty happy about that for a puzzle of this caliber. :-D

[@hisham_hm]

33:39 "Now what does that mean, though?" That means that Simon got his Beatles knowledge mixed up, by calling them the Lennon/McCartney of Sudoku then mentioning a George Harrison composition :)

[@EnjoyPA]

I came here to say this. I should have known someone else would have noticed...

[@travholt]

8:41: "This, I suspect, has been added later to disambiguate some pattern that occurs towards the end of the grid …" Oh, how wrong you were! :-D

[@JalebJay]

29:17 was stopped up with ignoring a lot pairs solved for some reason.

[@adrianhead6272]

Forced geometry and a hint of logic - completed in 22m57s.

[@glennmelven3414]

Mr. Menace creates a puzzle that finally rolls over and lets you tickle its tummy. OK.

[@SpeedyBozar]

I have been thinking about the uniqueness all day and I think it is a very wrong approach to any puzzle in general. Whenever there is a way to know solution based on the properties of output and not input, it is just bad. Like building a house from the roof etc. So if we know there is a solution where all digits are fixed to certain places (being called uniqueness in the video), then the puzzle has to be designed in such a way that we can never use this knowledge to make any advancement in solving. But what I think is much much better approach is to allow uncertainty which means the final solution does not need to have all digits fixed. I think not allowing solutions where not all numbers are fixed is madness, it is extreme restrictions to puzzle possibilities. I make my own puzzles and it never even occured to me to do this to myself. I design puzzles in such a way that they usually have many forms of solutions and usually the solutions are not equal to each other so the better solver most of the time finds better solutions.

[@jimminijillickers7062]

Simon, just curious, how many times have you made a mistake while filming and so didn't use that video/puzzle?

[@0Clewi0]

stuck for so long trying to crack the puzzle and I just needed to color box 1

[@peteradawson6576]

I remember "The Sound of Thunder" by Ray Bradbury.

[@tahvenduustalu3147]

Why don't you want to use uniqueness? Uniqueness tricks are to me some of the coolest and most beautiful ideas in Sudoku.

[@kathyjohnson2043]

And it seems to me to be a form of deductive inference. I may be wrong though.

[@RichSmith77]

Just my views... It makes an assumption that the puzzle only has one solution. A good, hand-crafted puzzle should have a logical path to reach the solution that doesn't require this assumption. The puzzle setter couldn't assume a unique solution. They had to be able to prove it when creating the puzzle. I see it as part of the challenge to try and do the same. (Although, admittedly, computers can brute force it to confirm how many solutions exist. I still think a setter worth their salt will ensure there's a human findable logical path to a unique solution.) By relying on the assumption, you may be using a short-cut that avoids some interesting logic that the setter hoped you would find. If your aim is to reach a solution as quickly as possible, then that's fine, but if you're solving because you enjoy solving, why reduce that enjoyment by taking a short-cut? I still get some satisfaction from spotting when uniqueness could be used. But I'll then try my best to ignore it and find an alternative path.

[@checler5428]

First time i finished a puzzle before you 29:11 :)

[@JohnRandomness105]

12:20 -- Try adding the two dominoes in the central box. You get a maximum for the sum as well. 13:05 -- Can we rule out 16? 16 in one domino and 14 in the other? (The maximum of the sum is ...) Whoops, sorry. Yes you can. The 6789 dominoes must be at least 15 and at most 17.

[@SjorsHoukes]

Yay! Managed to finish this one by myself. But… I did end up with a deadly pattern of 5s and 3s at the end, that was resolvable either way. Does this puzzle have 2 solutions?

[@SjorsHoukes]

Never mind… seems I messed up somewhere, but still ended up with a solution that the sudokupad accepted.

[@TheClawNinja]

Simon is a wizard. Confirmed at 35:15

[@_-_-Sipita-_-_]

30:35 for me. that 9 i missed

[@michaelhoffman2011]

That was a very fun puzzle. I see there was no april fools puzzle this year haha.

[@itsmeagain1745]

It's yet to come - this puzzle is from thursday 31 march in the UK.

[@pick6and129]

Can lines have repeat digits?

[@RichSmith77]

Yes

[@NekuraCa]

As soon as you got the line was 15 you could have filled the line as 12345

[@LednacekZ]

27:33 for me. quite hard, i think.

[@mikepictor]

24:23 why isn't it a 9? That domino could still be 8/9

[@alienrenders]

There are two dominos on lines in box 5 where one adds to 14 and the other to 15. The total is 29. There's only one way to do that (5+9 and 7+8). So when he removed the 5 from one cell, it's counterpart 9 can also be removed. An 8+9 pair would break the puzzle as it would leave 11 on the cells on lines in box 2 or 4 and it has to add to at least 15 (because the other lines have 5 cells and 5 cells adds up to at least 15).

[@RichSmith77]

(Simon's explanation @ 23:10)

[@seantaft3853]

Did anyone bother to point out that this started with 3 in the Corner losing its religion?

[@johnnycashless4758]

Simon said ( nice ! ) ! Nice one , si xD Really nice actually :p

[@RoderickEtheria]

Puzzle was fun, took me 31:47.

[@Chriib]

An argument for not using uniqueness is that one wants to proof that there is only one unique solution. If you solve a puzzle using uniqueness you have not proven that there is only one solution to the puzzle.

[@Pritchie45]

60 minutes

[@topilinkala1594]

First Simon proves that r7c2 can't be 6 because the sum on the line would be too high. Then he proves that 9 can't go there because the sum of the line would be too high. Then he proves that 8 can't go there because.... and finaly that 7 can't go there because... Why didn't he tell when trying 9 there that it is impossible because 6 already made the sum too big and used the same argument for 8 and 7? Does he think that the viewers are stupid?

[@maverickstclare3756]

just don't introduce Yoko Sudono

[@taekim8759]

i cant understand how you solve this in 40 minutes and how i cant do it for 6 hours..............

[@MLWJ1993]

"Not in normal Sudoku at least". Simon, I think that needs to be specified much more these days given the next Sudoku becomes even crazier than the last. The "special" Sudoku's have become quite "normal" to me 😐 In fact, vanilla Sudoku is pretty boring nowadays.

[@theunwelcome]

Simon going on and on about not using uniqueness to solve the part that could easily be done via the overlap in box 1

[@RichSmith77]

How does the overlap in box 1 prevent orange being 7,8 (at around 29:00)? Overlapping digit could be 8, with yellow being 6, no?

[@justsomeguywhoneverdies9210]

@@RichSmith77by "uniqueness", orange squares would be 6, 9 pair. The overlap would be 9

[@RichSmith77]

@@justsomeguywhoneverdies9210 I know. That was Simon's available deduction, if he allowed himself to use uniqueness. OP seemed to be suggesting it could be got another way, without using uniqueness. I couldn't see how.

[@JohnCater5]

Hearing about 45 as “the secret I only tell to special people” in every one of Simon’s solves, is getting a bit boring now.

[@longwaytotipperary]

Not for me - I ❤ it!!

[@bezowee]

@@longwaytotipperary i'm always happy that I'm special 😁

[@lauracortes7720]

not for meeeeee!

[@stevenape377]

I'm with the girls! I will always be happy I'm one of Simon's favourite people.

[@longwaytotipperary]

@@stevenape377 Welcome to our group! 🤗