Hello, GoodCity here! I was not expecting this puzzle to be featured so quickly, so thanks a lot to those who recommended it. I usually like to create puzzles and then think of a song that can go along with it. For this one, I tried to develop a ruleset that would match the song! Thank you, Simon, for this wonderful solution; I really appreciated the use of modularity to clarify some explanations. I had a great week for my debut, with both Simon and Mark (who solved one of my puzzles earlier this week).
Yes, the use of modularity was genius. Your puzzle was fascinating. I used SET to solve it (starting from row 4 + box 1), and my first digit was *9* in *r4c1.*
New to the channel (you can thank Numberphile for that!), loving it so far. There's something really endearing to me about how you say "The way to play is to click the link, but now I get to play, so let's get cracking!" every time
It’s a secret code that means “now stop this video before I spoil how to solve it” Also it really nice having someone else read the rules, sometimes I try and fail to break in to a puzzle but when I stare at the grid as Simon reads me the rules I see something that means I can now break in.
Just commenting on the onion explanation: when I said yesterday that Simon is a *great* Sudoku youtuber because he makes *us* feel smart, this was exactly what I was talking about. I saw the high digits thing very early. But I would never have thought of it if he hadn’t highlighted the five groups and made a point of the fact that there were five - yes he spent 45 minutes working through the low digits, but he made the space to notice “huh, there are only 6 circles *not* part of those 5 groups - is it even possible to put a 9 in?” And the first digit I saw was r6c2 had to be a 7 (while he was still talking about those 9 empties in the swordfish). So, Simon, if you read these: don’t ever apologise for doing things the long way. It leaves your viewers space to see the shortcuts for ourselves, and to feel really smart for doing so 💕
This is one of those puzzles where Simon and my solve differed in many ways, but still had a similar time. I was just a couple minutes longer than him at 37:40. One thing I noticed immediately working on box 1 was that 3 can never be in a 2 cell cage, and 1 and 2 can only be with each other in a 2 cell cage. I was surprised I never heard Simon mention either of those things. And I absolutely loved how Simon used the box/cage logic to get the 1 in r6c3. I got that cell by first determining the possible values of the cages in box 8, determining what the two digits in r6c45 had to sum to, and then taking the leftover for row 6. Great setting and solve in this one!
A very nice puzzle indeed. I started in box 9, and noticed that a 2-cell cage never has a 3 in it (it is either 12, 49, 58 or 67). That places a 3 in the 4-cell cage, which immeadiately exludes it being a 30 cage. Hence a 7 can be placed in box 8.
Very nice setting. Modulo math is fun. Here's a little deduction for you - in this ruleset, a 3 cannot appear in a size 2 cage. I found this box 9, leading to the conclusion that the bottom cage should contain a 3, so it cannot sum to 30.
Nice to see this one featured! If you like grids full of cages without totals then I'd highly recommend Buttered Cat Paradox, very hard but satisfying puzzle, it could be a good Patreon bonus puzzle.
This was fascinating. I loved the math-y features, and whether or not you started in the optimal place, Simon, I loved watching you work through the logic of this. Thank you so much for a great video!
Really enjoyed this one. I got in a bit early with one digit that was incorrect but once I sat back and thought about it, it all made sense. Thanks guys. Great channel
Made good progress at the beginning, then got stuck. Started to watch Simon's solve when I realized I missed something obvious in box 1 that he found, paused the watch and was able to finish the puzzle in 38:28 (conflict checker off). Probably could have shaved 10 minutes off if I'd noticed the deduction earlier. 😅 Wonderful puzzle from GoodCity!
A very fun puzzle for me, though I definitely stumbled through the modular arithmetic with thinking through all the 13/23/3 options haha. Ended up with a 70minute time over two sessions today, which I’m quite happy with. Also wanted to leave a comment about how much I enjoyed the Fog of War Kickstarter, which I picked away at during my holidays. Such a delight to read and solve!
This was fun! Thank you for sharing this puzzle. I often make mistakes when there’s much math and penciling involved. I lose track of details or forget possibilities. This looked like the type of complicated puzzle ripe for small errors. But it’s simpler than it looks (while still being fun and requiring thought throughout). And I didn’t make any silly mistakes until near the end. I did have the killer calculator turned on, since I didn’t have a pencil and paper nearby and my working memory is faulty. (It helped me remember whether I’d ruled out 13, 23, or something in the 30s.) And I often switched over to my calculator app (I can do many sums in my head, but again, I lose track if the calculation takes has too many steps!) The app makes these sudoku more accesible for me. I get to have fun doing the logic and math. And I can hit the checkmark to catch mistakes just a couple of moves past my error instead of after 16 wrong moves. (Since I forget exactly what I did wrong almost as soon as I undo it, I don’t consider this cheating-more like a “rewind, now pay close attention and delete some pencils marks!” button.) My thanks to you, Sven, and GoodCity!
The modularity trick wirh adding up the 3s was very useful, but I don’t think quite necessary for this puzzle. I solved it in just a few minutes longer than Simon and I didn’t spot this relation at all. I was instead coloring 3, 13 and 23 cages in different colors and figuring out what digits can or cannot go in.
I made some decent progress on this one by myself, especially once I figured out the modulo arithmetic trick. Eventually got stuck and came here, only to be unstuck immediately when Simon found the 4/9 domino in column 2! I don’t know how I missed that!
59:29, was surprised that I was able to start this (though I did check my work a couple of times to make sure I wasn't going down the wrong path), was surprised how long it took me to figure out the two 13 cages in Box 3 at the end.
27:25 "So this is a one by sudoku" - This was really confusing to me. Why did the 5-cell cage need a 1 in it? Thinking about it more, what made sense was: That cell was 1, 2, 3, or 8. It couldn't be an 8 because of the 8 in row 9. The 23 pair in column 2 had one digit in box 5 and one digit in the cage with the cell in question, so both of those are ruled out. The only digit left is a 1, by elimination. I re-watched that section a couple of times before it made sense.
Simon's reasoning was explained between 27:25 and 27:45. Whatever digit goes in that cell has to also appear in box -9- 7 somewhere. It cannot repeat in the column, nor in the cage. That limits where it can appear in box 9 to either column 1 or r7c2. Those four cells are known to be 1479. The only one of those not already appearing in box 4 is 1. (Edit: box 7, not box 9)
Simon's point was that by sudoku the green cell in box 4 also had to go in box 7. If the digit in that cell was (say) a 3, you end up not being able to place a 3 anywhere in box 7. So 3 is ruled out 'by sudoku'. As is every other possible digit except 1.
'Twas neither a curse nor a blessing. The solve was both fun and distressing. Cell 2:7 was mixed. I guessed that it was six. And I really don't like when I'm guessing.
Finished in 38:54. Man, I was stuck for the longest time in box 3 because I first messed up what the digits in the large cage had to add up to (I had it in my mind that they had to add up to 13 instead of 19), and then after that I had 2 possible solutions because I didn't exclude all the digits in box 2 in the large cage because I had taken care of that when it "added up to 13" and didn't correctly do that when I had to recalculate it. Fun puzzle, but man I made it so frustrating by messing up twice :(....
28:51 ... It can't, because the cage plus row 9 column 3 sums to 22 which is less than 30 (Edit: actually 25, I wrote 22 because that's what Simon said right before he asked the question)
I go a different solution than what is supposed to be. I double checked and every cage is correct (adds up to 3, 13,23, or 3x), but it claims I missed something. the top right box I but 8 in r1c7, 5 in r1 c8, and 6 in r2 c8. this changes the following by flipping: r1 c1 and r2 c1, r1 c6 and r2 c6, r4 c7-9, r5 c7-9, r6 c8-9, r7 c8-9, r8 c8-9, r9 c7-9, all of c9.
Very cool! Actually pretty doable, the only part I got hung up on for a bit was the end, disambiguating the c9r1-3 cage. But that wasn't too complicated either, just didn't see it for a while.
Given the theme on 3s, I would have been VERY disappointed if there wasn't a 3 in the corner. I was still slightly disappointed that there weren't two of them, but that can be forgiven 😃
You keep on telling us you're going to be streaming but you never say where or at what time. I'd love to but I don't know whether it's on twitch, youtube, or elsewhere, and when, and there's no link in the description for this.
Except this wasn't multiplication; it was a 2-digit number where one digit is a 3, and the other could be anything (including another 3) Positional notation is definitely NOT commutative.
Hello, GoodCity here! I was not expecting this puzzle to be featured so quickly, so thanks a lot to those who recommended it. I usually like to create puzzles and then think of a song that can go along with it. For this one, I tried to develop a ruleset that would match the song! Thank you, Simon, for this wonderful solution; I really appreciated the use of modularity to clarify some explanations.
I had a great week for my debut, with both Simon and Mark (who solved one of my puzzles earlier this week).
Congratulations again!
Unlike Diamonds, I was actually able to crack this one. :)
Yes, the use of modularity was genius. Your puzzle was fascinating. I used SET to solve it (starting from row 4 + box 1), and my first digit was *9* in *r4c1.*
Threeller?
I loved the fact that the grid is completely empty, its only the arrangment of cages that gives one a unique solution
I had a lot fun solving it. It’s a great puzzle. Thank you for making it sir.
That was a ton of fun. The break-in was interesting but very do-able and then the logic just flowed naturally from there. Excellent puzzle.
New to the channel (you can thank Numberphile for that!), loving it so far.
There's something really endearing to me about how you say "The way to play is to click the link, but now I get to play, so let's get cracking!" every time
It’s a secret code that means “now stop this video before I spoil how to solve it”
Also it really nice having someone else read the rules, sometimes I try and fail to break in to a puzzle but when I stare at the grid as Simon reads me the rules I see something that means I can now break in.
Just commenting on the onion explanation: when I said yesterday that Simon is a *great* Sudoku youtuber because he makes *us* feel smart, this was exactly what I was talking about.
I saw the high digits thing very early. But I would never have thought of it if he hadn’t highlighted the five groups and made a point of the fact that there were five - yes he spent 45 minutes working through the low digits, but he made the space to notice “huh, there are only 6 circles *not* part of those 5 groups - is it even possible to put a 9 in?” And the first digit I saw was r6c2 had to be a 7 (while he was still talking about those 9 empties in the swordfish).
So, Simon, if you read these: don’t ever apologise for doing things the long way. It leaves your viewers space to see the shortcuts for ourselves, and to feel really smart for doing so 💕
One of the rare cases where I've solved the puzzle before it being featured on CTC. Quite a fun puzzle that everyone should try
That was fun. Well done GoodCity - what a way to make a debut!
This is one of those puzzles where Simon and my solve differed in many ways, but still had a similar time. I was just a couple minutes longer than him at 37:40. One thing I noticed immediately working on box 1 was that 3 can never be in a 2 cell cage, and 1 and 2 can only be with each other in a 2 cell cage. I was surprised I never heard Simon mention either of those things. And I absolutely loved how Simon used the box/cage logic to get the 1 in r6c3. I got that cell by first determining the possible values of the cages in box 8, determining what the two digits in r6c45 had to sum to, and then taking the leftover for row 6. Great setting and solve in this one!
Thank you, Simon. I consider this your best solve in months, I enjoyed it throughout. Reminded me why I fell in love with CTC.
A very nice puzzle indeed. I started in box 9, and noticed that a 2-cell cage never has a 3 in it (it is either 12, 49, 58 or 67). That places a 3 in the 4-cell cage, which immeadiately exludes it being a 30 cage. Hence a 7 can be placed in box 8.
I love these heavily mathematical puzzles, where Simon can dance around the grid in joy 😊
Very nice setting. Modulo math is fun.
Here's a little deduction for you - in this ruleset, a 3 cannot appear in a size 2 cage.
I found this box 9, leading to the conclusion that the bottom cage should contain a 3, so it cannot sum to 30.
I enjoyed watching Simon solve this!
Nice to see this one featured! If you like grids full of cages without totals then I'd highly recommend Buttered Cat Paradox, very hard but satisfying puzzle, it could be a good Patreon bonus puzzle.
Fool on Hill is a tremendous solver, and appreciative of logic.
This was fascinating. I loved the math-y features, and whether or not you started in the optimal place, Simon, I loved watching you work through the logic of this. Thank you so much for a great video!
Nice to see a killer sudoku with such an interesting ruleset. Very simple to understand, and a nice solve from Simon.
Sven’s killer calculator was an absolute godsend on this one! 63:50
Fascinating puzzle and concept. Excellent solution Simon.
Really enjoyed this one. I got in a bit early with one digit that was incorrect but once I sat back and thought about it, it all made sense. Thanks guys. Great channel
Made good progress at the beginning, then got stuck. Started to watch Simon's solve when I realized I missed something obvious in box 1 that he found, paused the watch and was able to finish the puzzle in 38:28 (conflict checker off). Probably could have shaved 10 minutes off if I'd noticed the deduction earlier. 😅 Wonderful puzzle from GoodCity!
A very fun puzzle for me, though I definitely stumbled through the modular arithmetic with thinking through all the 13/23/3 options haha. Ended up with a 70minute time over two sessions today, which I’m quite happy with.
Also wanted to leave a comment about how much I enjoyed the Fog of War Kickstarter, which I picked away at during my holidays. Such a delight to read and solve!
12:25
possibly simpler:
4 cages, each ending in 3, sum must end in 2. that's 42 (no), 52 (possible), 62 (no). subtract 45 to get 7
That is a good break in for yesterday’s puzzle. Nice logic
Excellent puzzle - Always just enough to get you to the next step without feeling frustrated.
I (a Canadian) have started saying “I haven’t a Scooby Doo” when I don’t know something. Really hoping it catches on over here
This was fun! Thank you for sharing this puzzle. I often make mistakes when there’s much math and penciling involved. I lose track of details or forget possibilities. This looked like the type of complicated puzzle ripe for small errors. But it’s simpler than it looks (while still being fun and requiring thought throughout). And I didn’t make any silly mistakes until near the end.
I did have the killer calculator turned on, since I didn’t have a pencil and paper nearby and my working memory is faulty. (It helped me remember whether I’d ruled out 13, 23, or something in the 30s.) And I often switched over to my calculator app (I can do many sums in my head, but again, I lose track if the calculation takes has too many steps!)
The app makes these sudoku more accesible for me. I get to have fun doing the logic and math. And I can hit the checkmark to catch mistakes just a couple of moves past my error instead of after 16 wrong moves. (Since I forget exactly what I did wrong almost as soon as I undo it, I don’t consider this cheating-more like a “rewind, now pay close attention and delete some pencils marks!” button.)
My thanks to you, Sven, and GoodCity!
Thriller puzzle gives me thrills, I enjoyed this
This looked very daunting, but im kicking myself that i didnt have a go at it! My brain is very modulo friendly, and i think id have had a blast
Good mental arithmetic work-out, thanks.
Lovely puzzle. Really enjoyed Simon’s solve.
15:15 for me. Very nice puzzle!!
I love how he always keeps the ‘secret’
The modularity trick wirh adding up the 3s was very useful, but I don’t think quite necessary for this puzzle. I solved it in just a few minutes longer than Simon and I didn’t spot this relation at all. I was instead coloring 3, 13 and 23 cages in different colors and figuring out what digits can or cannot go in.
Not a difficult puzzle but a lot of fun to solve. Thanks for sharing it
Great to see a new ruleset 👍
Very beautiful puzzle.
I made some decent progress on this one by myself, especially once I figured out the modulo arithmetic trick. Eventually got stuck and came here, only to be unstuck immediately when Simon found the 4/9 domino in column 2! I don’t know how I missed that!
59:29, was surprised that I was able to start this (though I did check my work a couple of times to make sure I wasn't going down the wrong path), was surprised how long it took me to figure out the two 13 cages in Box 3 at the end.
25:44 for me. With a puzzle like this, no step is particularly difficult, but noticing in which part of the grid the next step occurs can very tricky.
27:25 "So this is a one by sudoku" - This was really confusing to me. Why did the 5-cell cage need a 1 in it?
Thinking about it more, what made sense was: That cell was 1, 2, 3, or 8. It couldn't be an 8 because of the 8 in row 9. The 23 pair in column 2 had one digit in box 5 and one digit in the cage with the cell in question, so both of those are ruled out. The only digit left is a 1, by elimination.
I re-watched that section a couple of times before it made sense.
Simon's reasoning was explained between 27:25 and 27:45. Whatever digit goes in that cell has to also appear in box -9- 7 somewhere. It cannot repeat in the column, nor in the cage. That limits where it can appear in box 9 to either column 1 or r7c2. Those four cells are known to be 1479. The only one of those not already appearing in box 4 is 1.
(Edit: box 7, not box 9)
Simon's point was that by sudoku the green cell in box 4 also had to go in box 7. If the digit in that cell was (say) a 3, you end up not being able to place a 3 anywhere in box 7. So 3 is ruled out 'by sudoku'. As is every other possible digit except 1.
'Twas neither a curse nor a blessing.
The solve was both fun and distressing.
Cell 2:7 was mixed.
I guessed that it was six.
And I really don't like when I'm guessing.
57:16 for me. That was tricky! Just on the edge of being too hard for me. Got really stuck at the end with box 3 but glad I persevered.
Excellent puzzle, thank you!
26:14 for me. i am very happy with the solve.
Finished in 34:39. Fun puzzle!
I feel like this ruleset would work well with the positive/negative yin yang rules from gdc's puzzle a few days ago.
Have to restart my solve. Forgot the possibility of just having 3 as the sum!
19:27 with a few bad math places
(some odd reason I thought I needed X3*5 ended with 5 when I needed it to sum to 0)
Great puzzle! I'm pretty sure this is not Goodcity's debut. Mark did one of their puzzles which had 7 arrow circles, all in box 5.
So how do I say this in the most kind way so Simon will read the comment?? Nice solve!!! (not in all caps!)
Gave it a 5-minute stare and a few sparse pencil-marks before giving in to this being a break in and solve I got to watch instead of figure out
Finished in 38:54. Man, I was stuck for the longest time in box 3 because I first messed up what the digits in the large cage had to add up to (I had it in my mind that they had to add up to 13 instead of 19), and then after that I had 2 possible solutions because I didn't exclude all the digits in box 2 in the large cage because I had taken care of that when it "added up to 13" and didn't correctly do that when I had to recalculate it.
Fun puzzle, but man I made it so frustrating by messing up twice :(....
24:54 for me, I really liked it.
28:51 ...
It can't, because the cage plus row 9 column 3 sums to 22 which is less than 30 (Edit: actually 25, I wrote 22 because that's what Simon said right before he asked the question)
"I don't know what that's called"
It's an x-wing!!! it's actually the easiest to spot x-wing too.
Author missed the chance to call it "Threeller"
I was just about to post this. It should have more likes. Good call.
I go a different solution than what is supposed to be. I double checked and every cage is correct (adds up to 3, 13,23, or 3x), but it claims I missed something. the top right box I but 8 in r1c7, 5 in r1 c8, and 6 in r2 c8. this changes the following by flipping: r1 c1 and r2 c1, r1 c6 and r2 c6, r4 c7-9, r5 c7-9, r6 c8-9, r7 c8-9, r8 c8-9, r9 c7-9, all of c9.
Took me 37 minutes. A fun solve.
Very cool! Actually pretty doable, the only part I got hung up on for a bit was the end, disambiguating the c9r1-3 cage. But that wasn't too complicated either, just didn't see it for a while.
Just watching the end, the 7s were deduceable in isolation, that was my break-in.
Brute forced my way through, finishing It was worth the effort
Very nice puzzle about 3. Not only all cages had 3 in their sum, we had a 3 in the corner as well! 😅
3 stars difficulty too!
@@AngryKettle 😆
Given the theme on 3s, I would have been VERY disappointed if there wasn't a 3 in the corner. I was still slightly disappointed that there weren't two of them, but that can be forgiven 😃
40:09 for me. Nice puzzle!
29:16 for me. Amazing one :)
14:11 for me. cool sudkoyu.
If only I could sum three numbers correctly :D
50:11 for me
nice puzzle
Hi tanks for the mention this is Joel from México and my age is the secret
I hear Simon say we have decided that 28 does not contain a 3. Good day's work everyone.
Panache 😁💕
60:41 for me!
You keep on telling us you're going to be streaming but you never say where or at what time. I'd love to but I don't know whether it's on twitch, youtube, or elsewhere, and when, and there's no link in the description for this.
nice puzzle - took me 64 min though :)
Fun! Took 27 minutes.
awesome
28:40 for me - my time didn't start or end in a 3.
40:25 for me
Finished in 33:33 😂
83 minutes
25 Chances to sing 'That's 3 in the top left corner' and none used thus far. I'm disappointed.
Fair point!!!
Where is the 33!! sum cage? That would be a rather large cage.
X3 and 3X are the same thing. Multiplication is communitive.
Except this wasn't multiplication; it was a 2-digit number where one digit is a 3, and the other could be anything (including another 3) Positional notation is definitely NOT commutative.
That would be written ?3 and 3?, 3X and X3 is multiplication.@@Qurqirish_Dragon
Plus, X is not constant, it is not always a 1 for example. The notation is simply incorrect.
How long is Simon going to keep dragging that other guy along on the channel? It’s really time for him to move on.
"Not too difficult"...? 80 minutes ending in a bifurcation :( but great puzzle