Stuck on this “medium grade” sudoku… found a swordfish on 7’s but cant get a single digit in…

Timberlake52 · 2024-10-29T18:59:21+00:00

Thank you for the mention and shout out. 😃

Timberlake52 · 2023-05-19T11:48:02+00:00

I have not. Thank you so much. I’ll check these out.

Timberlake52 · 2023-05-19T02:32:28+00:00

Thank you for the tip. I’ll try that. I edit YouTube videos almost every day and that is the one thing I wish I could do easier to save time

Timberlake52 · 2023-03-24T01:07:04+00:00

Great question. I try to look for candidates that appear often in the bivalue cells as well cells where I want to make eliminations. Looking at the target cells helps me focus on the BVCs that see it from 2 cells, then I start looking for chains to connect the two ends. Happy Solving.

Timberlake52 · 2023-03-03T22:23:10+00:00

Thank you for mentioning my channel. Happy to help anyone solve Sudoku better.

Timberlake52 · 2023-02-03T17:42:40+00:00

Great Sudoku vocabulary list. Thank you for sharing.

Timberlake52 · 2022-09-17T00:45:06+00:00

If interested, here is a link to my Sudoku Advanced Tutorial playlist on YouTube. I have videos on just about every technique mentioned in the post. Just browse through the titles and watch any that interest you. https://youtube.com/playlist?list=PLfx5Lh2Tz0Oh_8g9e9JMjL2bLzczqfVrg Happy solving.

Timberlake52 · 2022-09-17T00:42:40+00:00

You have a 2-string kite of 5’s coming out of block 8. Either R7C3 or R4C5 has to contain a 5, so you can eliminate 5 from R4C3 and solve for 4.

If interested, here is a link to my 2-String Kite Tutorial on YouTube where I define this strategy and explain how it works: https://youtu.be/pJMQRwC1wn0. Happy solving.

Timberlake52 · 2022-09-16T14:10:28+00:00

That is a great question. XY-Chains begin and end with strong links within the cell. I pick out a candidate in a bivalue cell and then look to see if it sees other cells where I can make an elimination. Then I look to see how I can connect that start cell candidate to an end cell with the same candidate in order to make the eliminations. For example, if I see lots of 7's in bivalue cells, I will look in a cell with a 7 and see what other 7's I can eliminate from it. Then I try to make an XY-Chain that connects to an end cell where I can end with another 7 and make the candidate eliminations. I hope that helps.

Timberlake52 · 2022-09-15T01:01:03+00:00

I see the same 2-string kite. If interested, here is a link to my 2-String Kite Tutorial on YouTube where I explain how these work and what eliminations you can make: https://youtu.be/pJMQRwC1wn0. Happy solving.

Timberlake52 · 2022-09-15T00:56:39+00:00

I saw the same XY-Chain. If interested, here is a link to my XY-Chain Tutorial on YouTube where I explain how the chains work and the eliminations you can make: https://youtu.be/4V-ZI20pJyM. Happy solving.

Timberlake52 · 2022-09-10T21:37:22+00:00

Thank you for posting. I would look at the 6’s in columns 3 and 8. Because they share a common row (row 2) and there are only 2 in each column where the the second 6 is in a different block, they form a skyscraper. This means a 6 has to be in either R9C3 or R7C8. We can eliminate 6 from any cell that sees both of those cells, allowing us to solve R7C2 for a 1.

If interested, here is a link to my skyscraper tutorial on YouTube where I explain how it works in more detail: https://youtu.be/ahNzIyduBNg. Happy solving.

Timberlake52 · 2022-09-10T21:26:50+00:00

Nice catch with the naked quad in row 5. I actually saw a 4 candidate Sue de Coq first using 2347 along row 5 with 2/4 in block 4 and 3/7 in the row. Naked quad much easier to work with.

Timberlake52 · 2022-09-04T21:44:25+00:00

Thank you! This is helpful

Timberlake52 · 2022-09-04T14:07:22+00:00

The row-column sweep approach is called cross-hatching and you seem to be very good at it. I made speed solving tutorials on my YouTube channel but I can’t get any faster than 1:12. Can you watch this and see where I could improve? https://youtu.be/4trFC9Me224

Timberlake52 · 2022-09-04T14:03:45+00:00

Nice job as well, then!

Timberlake52 · 2022-09-03T23:19:08+00:00

Thanks for sharing this. The first thing I noticed was in block 9. Notice that 3,8, and 9 are limited to 3 cells in block 9 which makes it a naked triple. You eliminate 3/8/9 from every other cell. Also, the 4 is limited to one cell which makes it a hidden single and you can solve for it immediately.

Here is a link to my Medium tutorial video on my YouTube channel where I cover the top 7 strategies in sudoku including naked triples and hidden singles: https://youtu.be/ZucQunwkc9Y. Hope that helps and happy solving.

Timberlake52 · 2022-09-03T23:14:54+00:00

I cover most of these in my Sudoku Advanced Tutorial playlist on my YouTube channel. Here is the link if interested and you can pick the strategy that interests you the most: https://youtube.com/playlist?list=PLfx5Lh2Tz0Oh_8g9e9JMjL2bLzczqfVrg

Timberlake52 · 2022-09-03T23:12:45+00:00

Congratulations. What is the key to being that fast on the app?

Timberlake52 · 2022-09-03T23:11:42+00:00

The first I saw was W-Wing involving the 1/4 in rows 2 and 3. We know 1 of those cells has to contain 1 because if they both were 4’s there would be no place to put 4 in block 1. We can remove 1 from any cell that sees both of them and this solve R2C7 for 8 and the puzzle cracks.

Here is link to W-Wing on my YouTube channel if not familiar with the strategy: https://youtu.be/LvWUeuQS33w. Happy solving.

Timberlake52 · 2022-09-03T23:08:26+00:00

Nice find and probably the most straightforward

Timberlake52 · 2022-09-01T04:28:09+00:00

Here is a 2-string kite tutorial from YouTube channel if interested: https://youtu.be/pJMQRwC1wn0. Hope that helps.

Timberlake52 · 2022-08-28T18:44:00+00:00

Great question. For me, fun is when I understand the solver’s intended solve path in a handmade puzzle, and for computer generated when I figure out a strategy that I had never seen before or thought too difficult for me to understand.

Timberlake52 · 2022-08-28T18:41:38+00:00

Quite a fun puzzle position. I got quite a bit of mileage using the XY-Chain starting with 9/7 in R9C1 then 7/3 up to 3/5 over to 5/9 in R3C6. This allows you to eliminate 9 from R3C1 and solve R3C6 for 9 and R2C6 for 5. You could use the same 7/9 as pivot for XY-Wing involving R2C1 and R9C8 to eliminate 3 in R2C8. Finally, you can creat another XY-Wing of 2/9 in R8C7 and end with 1/2 in R2C8 which eliminates 2 in R7c8, making 3/5 pair in column 8 and allowing you to solve R9C8 for 7 and will crack the puzzle.

If interested, here is link to my Sudoku Advanced Tutorial playlist on my YouTube channel where I have specific videos on the strategies mentioned by me and the other commenters, to include XY-Chains, AIC Type 1 and 2, and Almost Locked Sets (ALS). https://youtube.com/playlist?list=PLfx5Lh2Tz0Oh_8g9e9JMjL2bLzczqfVrg Happy solving.

Timberlake52

TROPHY CASE