Who Makes The Best Sudoku Puzzles In The World?

We are delighted to showcase the first in a series of puzzles by Oku-Yama, one of Sudoku setters from Nikoli, the home of Japanese pencil puzzles. Oku-Yama's Sudoku puzzles are the finest we have ever solved and you'll be able to see more of them on CrackingTheCryptic over the coming months.

If you enjoy this sort of Sudoku you should take a look at Nikoli's website where puzzle collections are available:

@crypticcracking
@nikoli_official

[andyparkerson]

I am so glad you never leave a puzzle unfinished now. Much improved!

[SudokuGuy]

Well done. I love the way you found the X wing.

[lawrencekallal]

Nice puzzle as usual.

A nice force test solution, starting at 9:30, involves the 2 positions for the 7 in R3, C3, 5.

If the 7 is placed in C3 the 6 goes in C7. Following the 6, 7's we end up with 56 pair in the middle 3x3 block, and a 7 in C5.

So, there is a 7 in C5 aiming at the bottom block no matter which of the 2 positions is chosen for the 7 in R3.

This gives the 7 pair in the bottom block which resolves the 678 in the bottom right hand block. That was enough to get the puzzle going nicely.

[goldenera]

at 6:54 we know from previous calculations, that the only values for cells (r2c3) and (r5c3) are 2 or 3. so why cant we place 2 straightaway knowing this in r5c3 and then place 3 in r2c3? may be this is where if you combine with David Mcneil's notation then you can see those 2 numbers. I agree it may get confusing if you are not careful.
beautiful indeed.

[lsmart]

Simon is obviously a brilliant Sudoku solver, but as I've noted elsewhere, he is often so quick to notice brilliant tricks that he ends up overlooking a much easier answer staring in his face. At 6:40, he goes on a 1.5 minute explanation as to why r2c3 must be a 3, when he could have done it in 5 seconds, since r2c3 and r5c3 must contain a 2 and a 3, and r5c3 cannot be a 3 since r5 already has a 3 in it.

[goster]

That's a very nice puzzle indeed! And how do you even start with making these yourself, wow.

Looking forward to more, and Happy New Year to you and yours!

[glennmelven]

That x-wing on 7s was great. At first I couldn't figure out what it eliminated. Then I saw what you did, how a 7 was forced in C8 R7. And that broke the puzzle open.

[jagmarz]

One thing which you sort of discuss obliquely a lot is that puzzles can be designed. I'd love to hear some discussion about how one actually designs and sets a puzzle. That actually goes for crosswords, too.

[donnyh]

There's no link in the description to try this one 😢

[ragnes]

Sorry I don't understand how the 1 is getting there? 5:23 I really enjoy your solving technique.

[jrbr]

That 234 triple starting at 10:00 (ish) boggles my mind. I guess I don't understand why those numbers have to be triples.

[jeffbrunton]

Loved your logic for derive the triple in the middle column

But why not write it in?

[jeffbrunton]

Top left box., deriving the 3 was long winded

You had just said there were 23 pairs, but would not write them in yet

one of those was already reduced to a 2, resolving the 3 in the top left without all the complexity

[julieannmyers]

It's prettier if you solve rows 3 & 7 and columns 3 & 7 first... cool design.
Then fill in the 2x2 cell corners, etc.

[SudokuGuy]

I hae trouble about you knowing that a 1 in column 5 is only possible in block 2 cell 5 and 7.

[gebe]

Link is no bueno. Any other place similar?

[moshehim]

I hate it when you decide the logic has collapsed the puzzle, the rest would unfold on its own. Then I spend 20 minutes trying to finish it, and end up with 3 fives in a column...

[shane]

Yeah this dude's great but my problem is I'm just like one or two steps beneath being able to appreciate him.

[bluestar]

I don't fully get how you got 234 sets inn column 5. Could you please explain again.

[helgeb]

What is the program you are using to solve these puzzles?