I Tried The Internet’s Hardest Sudoku (11.9 MAX Rating)

In I Tried The Internet’s Hardest Sudoku (11.9 MAX Rating) SHC 274 by Smart Hobbies, I will show you how to solve the hardest Classic Sudoku I could find on the internet, Puzzle For Mathimagics by Coloin, which has a maximum 11.9 Sudoku Explainer Rating. I show you how to solve the internet’s hardest puzzle in 5 logical steps using everything I’ve learned about solving the world’s hardest Sudokus. I solve this puzzle and explain all the expert Sudoku tricks, Sudoku techniques, and Sudoku strategies as I apply them to the Sudoku game.
#play #learn #sudoku

I used the software program SudokuPad for this solving video. Puzzle link:

Check out original post here:

Check out Shye’s solve of this puzzle here:

Check out Smart Hobbies page on Harold Nolte’s Sudoku Primer website here:

Contact me here:
Discord: Timberlake#1905

Timestamps
0:00 Intro
00:24 It’s Solving Time
00:52 Puzzle Story
01:36 Step #1
09:22 Step #2
13:01 Step #3
19:19 Step #4
25:37 Step #5

Strategies demonstrated in this video:

Hidden Single
Naked Single
Full House
Pointing Pair
Naked Pair
Claiming Pair
Naked Triple
Trivalue Oddagon
Sudoku Fireworks
Remote Triple
Finned X-Wing
BUG+1

Let me know what you think and how you did in the comments below. Thank you so much for watching.

Timberlake

[SmartHobbies]

Timestamps
0:00 Intro
00:24 It’s Solving Time
00:52 Puzzle Story
01:36 Step #1
09:22 Step #2
13:01 Step #3
19:19 Step #4
25:37 Step #5

[paulakeay]

Took me an hour, but I completed it via logic and tenacity only, and I feel pretty pleased!

[grantfraser]

It was a little under 3 hours. I know you'll aak about strategy used so I've put some thought into this answer.

I filled in box 1 (minus 123) and recognized the oddagon problem. I reasoned that the 123's must be offset so I set about disproving 123 in row 7/box 8.

After that it was just a hard slog of trial and error eliminating best wrong guesses until one of them turned out to be right.

By that point I had enough. I usually set about showing that it's a unique solution but it's late, I'm tired, and I trust you.

I'll watch the actual solution tomorrow. I look forward to learning from it.

[compiling]

An easier way to see step 3 is to notice that the 3rd low digit in row 6 and column 7 both have to be in box 6, so you can find the remote triple by just colouring starting from that box.

Then if you don't remove the colouring, you can find a yellow-8 pair in boxes 6 and 7 that only works if yellow is a 3 due to the restriction on 8s, instead of doing the analysis again with x wings.

Nice puzzle. I needed a few hints to get through it, particularly step 1 since I've never seen that pattern before.

[tonyreno]

i got a solution, took nearly 2 hours (with several interruptions, so I don't know my real time, probably slightly over an hour). I haven't checked the rest of the video yet and wanted to write out my logic so I could check against it later.

I first marked the 123s in blocks 1, 2 and 4, then all the usual snyder marks. Then I looked in the full house on row 7 and noticed the 38 in C9 and the 123 in C4, 5.

Next I figured followed steps similar to the nearly-full-set to find that R1C4 and R2C2 had to be different from each other.

For next elimination step I figured where I put my 3 in block 2 would give the fastest tests, given R7, C7 and C9. and, sure enough, 3 anywhere other than R3 C6 failed fairly quickly. (but I was fairly unlucky as there were still a fair number of combinations). Once I got the 3 in R3C6 the eliminations came quickly and I was down to 2 potentials for block 4. First one failed.

I was happy that I was picking up speed-ups along the way. But I still used an embarrasing number of undos to solve it. I'm really looking forward to seeing the logic you've got on this.

[lrvogt]

The odds of ever seeing that symmetrical pattern are pretty small but figuring it out is key.

[BradJames]

I gave this puzzle a shot, even after reading the "strategies demonstrated in this video' list. My setup was very good; I filled in the blocks needed for the oddagon. But I couldn't figure it out because the 8, 9&6 in block 5 were in the cells that I needed. I lost interest at the next step though (and after spending an hour), when a magic birdie tells us to fill in column 7 and block 6.

[JohnRandomness]

I *think* that it took less than six hours to do the puzzle; I'm not sure. I began by placing digits greater than 3 in block 1, and cornermarking them in block 5. Of course, I saw the threat of the 123 topological loop, and worked to show that in block 5, two of 123 had to be in the same column or row. I also saw 1238 in row 7: 123 in block 8 limited 123 to one per column in block 5, and unambiguously broke the puzzle. That gave me 3 in block 9 and 8 in block 8. The same thing forced a 123 in R1C7, block 3.

Then came the digestive part of the problem. I placed A, B, and C in block 1 for 123. I immediately made an unwarranted assumption about block 4 and possibly block 2, and went a long ways before everything I tried crashed. Then I backtracked almost to the beginning and realized my mistake. I put the proper AB, AC, BC in blocks 2 and 4 and also created another set of letters, D, E, and F. I wound up progressing toward the combination C, D, and the digit in R1C7 which I labelled O -- while keeping the others as labels. It didn't confuse me as much as it should have.

Block 5 column 4 gave me this interesting logic: if R5C4 is 7 and R6C4 isn't 4, it led to one digit (4, 5, 7) in each row and column, leading to the broken 123 loop. If R5C4 is 123 and R6C4 isn't 4, it led to a quad of 123s in column 4. Therefore, R6C4 had to be 4. Similar logic led to R6C5 being 5.

15:10 This led to yellow and purple being different. Yellow was my O, the cell above purple was C, and D was next to it. I had an 8O pair in row 6 block 6, so purple couldn't be C or O -- it had to be D and blue had to be C.
21:20 I only resolved the 8s when I changed O to 3: the 83 was above the 3.
22:00 The O8 pair which became 38 immediately forced green to be 3. Defining R1C7 to be O immediately broke up any X-wing involving that cell.
24:50 I filled that square in block 3 far earlier: two versions, in fact. I centermarked ABC along with the 7 and 9s, and cornermarked DEF. I whittled it down to a 79CD square, and that led me to define R1C7 as O -- and motivated me into using CDO.
27:00 I finished by bifurcating on a 67 cell. The centermarked choice collided, so the cornermarks were correct.

[anaayoung]

Every step was hard.. Ha!
You used so many strategies to solve it. 🧐
Thanks for the solve, I enjoyed watching your video. 😎
And thanks for the donate!! You are a smart and kind person!!! 🤗☺

[Ton-Ekkapol-OO]

It's really difficult, Thank you teacher.

[kaylynnebingham]

I just watched this video along with all of your extreme puzzle videos, and none of them are as hard as the ones in my new book not one puzzle has an obvious answer and all of these have at least three or four right off the bat. I can’t even get that far. Is there any way that I could send you a few shots of these that you could maybe help me get started I’ve tried doing patterns. There’s no obvious patterns that I can find most of these I’m watching I can solve just by looking .this book it’s got me stumped. I don’t have readdit or was I able to use it? Is there any other way I could send you a few shots of these puzzles? I’m desperate thank you

[jacquespictet]

Nice trick, but the explanation is hard to follow. Basic principle: do not remove colors until they become useless. If you do so, the explanation of 7 in box five is quite simple, so is the three 123 in column 7, etc.

[davidrichards]

Dude your explanations are meandering and unclear. You're grasping in real time for words to explain what you're trying to say, which indicates to me that you're not well-prepared and/or not clear in your own mind what you are doing.

[zawilious]

That was easy, barely an inconvenience

[kv]

the ones are very easier ones. tough ones are with only 17 spots out of 81 filled

[francoisepichot]

Hello Timberlake. Great to view your extreme puzzles, thank you so much, but I got confuse by your first explanation because before listening to you I tried to solve the puzzle and filled (pencil and paper) all the cells. I of course noticed immediately the pattern 123 and thought of the trivalue oddagon but noticed that with the 896 in block 5 it was not going to be as easy as thought. Now your explanation assuming that you must absolutly keep the triplet 123 in columm 6 is not clear at all. Why not have one different digit in each column block 5 ?
It works having 4 R6C4 and 7 R4C5 and 5 R5C6 ... ??
Thank you so much in advance for your highly expected answer.

[phillipsinger]

One Issue: My color vision is such that I am unable to distinguish any difference between your purple or blue cells.

[ColoRadio]

How did you know to start at block 5? TIA Stay safe...

[michael]

3 in the center ez solve upper right corner

[Jcitsogams]

Wow! Astonishing Timberlake. Way out of my depth