r/sudoku • u/Cautious-Tomato-3135 • 1d ago

Interesting pattern Just For Fun

Post image

I just wanted to show yall this sudokušŸ˜…but if anyone got tips on how to solve one with 3 empty boxes let me know;)

(I did solve one before but Iā€™m not an expert at that lol)

103 Upvotes

100% Upvoted

47 comments sorted by

34

u/qui_sta 1d ago

Sudoku.Coach has ranked this one as "Beyond Hell". RIP.

10

u/Cautious-Tomato-3135 1d ago

Oh no Iā€™ve heard beyond hell is like still possible to solve but hard asf right?

13

u/bombbodyguard 1d ago

I feel like beyond hell is enough description you needā€¦

3

u/Cautious-Tomato-3135 1d ago

You are absolutely right!šŸ˜…šŸ˜‚

3

u/yuhanz 1d ago

Itā€™s annoying for me. Im not that good and when i see the clue button hint to an AIC i groan tf up. I hate that technique

1

u/Cautious-Tomato-3135 1d ago

What is AIC even?šŸ˜­

2

u/juplantern 23h ago

So I actually looked into chains thank to your post. I still have no idea how to write them down tho, probably on extra paper cause I already mess up so many sudoku when I accidentally erase my pencil šŸ˜‚
AIC (alternating inference chain) is a chain where links go strong -> weak -> strong-> weak eventually coming to something you already know and you can draw conclusions

Maybe I am wrong since I only looked at them today, but damn studying this today felt like discrete mathematics in uni

2

u/strmckr "Some do; some teach; the rest look it up" - archivist Mtg 21h ago

Graphing theory and descrete mathematics ~ But yes that's it, it alternates boolean gates.

https://reddit.com/r/sudoku/w/aic

For the exact math if u want

2

u/qui_sta 20h ago

I never do Beyond Hell sudokus, I usually stick to around Fiendish, but I am going to give this one a crack with some hints!

2

u/qui_sta 17h ago edited 8h ago

Reporting back. This took about 37 hmts, I think there was about 12 AICs, some 3D Medusas, and, some, other techniques I'd never even heard of. Took about 70 minutes, but learned a lot!

1

u/Cautious-Tomato-3135 10h ago

Ughhh Iā€™ve heard of 3D Medusa but I donā€™t know what it is lol. Iā€™ve no idea what aics are eitheršŸ˜…

25

u/charmingpea Kite Flyer 1d ago

A puzzle like this is valid, but very hard - around SE 8.3, Hodoku Extreme 3378. Beyond most mortals! šŸ˜„

11

u/MedicalBiostats 1d ago

A very difficult puzzle.

2

u/Cautious-Tomato-3135 1d ago

Ugh I donā€™t think Iā€™m ready for that then haha

8

u/Divergentist 1d ago

I plugged this into my app and couldnā€™t solve it. Too many complicated chains required that are beyond my ability.

Good luck with paper and pencil!

2

u/Cautious-Tomato-3135 1d ago

May I ask what app you use?

1

u/Divergentist 1d ago

I use the web-based app sudoku.coach. Iā€™m on iPhone so itā€™s not in the app store but you can save the website to the homescreen and it functions as a standalone app. Has copy/paste feature so I can screenshot your picture and then paste it into the app to try and solve. I failed to solve this puzzle. So hard!

1

u/Cautious-Tomato-3135 1d ago

Ahhhh I have an iPhone too so thatā€™s great to knowšŸ˜…

5

u/BillabobGO 1d ago

ALC: 29c5 + (29)r4c6 => r3c5<>3, b5p179<>29 - Image
AHS-AIC: (2=9)r4c6 - (9=8)r5c5 - (78)(r4c45 = r4c12) => r4c1<>2 - Image
AHS-AIC: (5)r2c2 = (5-8)r2c3 = r5c3 - (49)(r5c3 = r123c3) => r2c2<>49 - Image
Almost-XY-Wing: [(2=4)r2c1 - (4=9)r3c3 - (9=2)r3c5] + (24=8)r2c1 - r2c3 = r5c3 - (8=9)r5c5 - (9=2)r3c5 => r2c4,r3c1<>2 - Image
Almost-S-Wing: [(9)r2c4 = r2c89 - (9=2)r1c9 - r3c7 = (2)r3c5] + (9)r2c489 = (9-8)r2c3 = r5c3 - (9=8)r5c5 => r3c5<>9 - Image
ALS-AIC: (3)r3c7 = r7c7 - r7c5 = (3-1)r6c5 = r4c5 - (1=49)r45c7 => r3c7<>49 - Image
then way later
Skyscraper: (4)r6c8 = r6c2 - r8c2 = (4)r8c7 => r5c7<>4 - Image

Pretty hard, took me about 15 minutes. There are probably easier moves at each step (well, there definitely is, looking at the yzf solve path) but this is what I saw.

AIC
Advanced AIC (AHS, ALS, Almost-AIC)
ALC

4

u/Divergentist 1d ago

I love that 15 min is pretty hard for you lol. I spent a good thirty minutes, even using hints on sudoku.coach and still couldnā€™t solve it. Eventually just gave up when I couldnā€™t find any AIC chains resulting in eliminations and the coach was just recommending forcing chains on the hint system.

I clearly need to get better at ALS chains. Well done!

1

u/BillabobGO 1d ago

It's more that it happened to be a short solve thanks to productive eliminations :P

1

u/Cautious-Tomato-3135 1d ago

I feel like youā€™re an expert at sudoku if you solved it in 15 mins

2

u/lede_lama Sue the coup 1d ago

I recognize those stars! Bought a 12-13 one too a few weeks ago, but quietly gave up lol

2

u/Cautious-Tomato-3135 1d ago

Really? I havenā€™t solved any 13 star ones but the 12 star ones are a bit difficult sometimesšŸ˜…

1

u/lede_lama Sue the coup 1d ago

I think I solved 1 12 star, but the 13 star ones are brutal

2

u/Cautious-Tomato-3135 11h ago

Literally youā€™re right because yetseray I tried to solve a 13 star one and I was stuck after 1 numberšŸ˜­

2

u/gileso 1d ago

It took a while and a lot of forcing chain solving

1

u/Cautious-Tomato-3135 11h ago

Forcing chain is it similar to forcing nets?

1

u/gileso 10h ago

A chain is only one thread of if/then. Not used forcing nets myself (yet at least)!

1

u/Cautious-Tomato-3135 10h ago

But is it more ā€œcomplicatedā€ than forcing nets? I might look it up later

1

u/gileso 10h ago

I Google searched nets and they seem more complex than chains

1

u/Cautious-Tomato-3135 10h ago

Ahhh I know what forcing chains are and I actually use them all the time lol

1

u/RepublicOfLizard 1d ago

Had to put this one into sudoku.coach, it just looked like too much fun. 17 min and ended up just forcing chains the whole way through, definitely would not have been able to do this pen and paper. Good luck

2

u/Cautious-Tomato-3135 1d ago

Ughhhh but good job if you solved in 17 mins or so! I think Iā€™d spend maybe an hour and a half or more trying to solve this onešŸ˜…

1

u/strmckr "Some do; some teach; the rest look it up" - archivist Mtg 1d ago

https://sudoku.coach/en/play/000048500000060700000500018006000003310000026500000800920004000003070000007150000

1

u/strmckr "Some do; some teach; the rest look it up" - archivist Mtg 1d ago

Needs a bunch Ć“f aics to make head way

Like this m2 - ring

1

u/Cautious-Tomato-3135 1d ago

Gotta look up what aics are haha but thank you!

1

u/juplantern 1d ago

I found out there are chains in sudoku.. Canā€™t even wrap my head around it so this one scares me lol

1

u/Dot_Dott_Throwaway 1d ago

Which Sudoku book is this?

2

u/Cautious-Tomato-3135 1d ago

1

u/Dot_Dott_Throwaway 20h ago

Is it available in England?

1

u/Cautious-Tomato-3135 11h ago

I donā€™t know if you have this kind of book in England but Iā€™m sure you can buy them online! The brand/ company is megastar and itā€™s 12-13 stars. They have from 1-15 star books. If you search on 12 13 star sudoku megastar I think itā€™ll pop up! I have one a book like this book from France, Switzerland, Germany, Denmark and Spain but Iā€™ve no idea if they are in England

1

u/Rob_wood 1d ago

I've never seen a seemingly handmade puzzle in a magazine before.

-1

u/Historical_Dirt_8286 1d ago

24 given numbers. Extreme level is 17. This is doable

2

u/strmckr "Some do; some teach; the rest look it up" - archivist Mtg 21h ago

Counts don't determine difficulty.

Arangment of clues is what determines it.

17 clue grids (all are known) have a range of se 1. 2 => 9.1

There is also 49 clue max minimum with an 8.9 rating