This is the archive of the old posts from Djape .Net, more or less as they used to be. Please go to djape.net to see the new website.

Diagonal Sudoku Wing X

By djape | Published: November 26, 2005
Instead, a very similar yet different variation – the true Wing X. This is not to be confused with the X-Wing solving technique! Wing X for Saturday, November 26 – this is the only place you can find these kind of Sudoku puzzles! Basically, not only do you have to fight against 5 interconnected Sudokus, but you also need to be carefull about the diagonals: ALL diagonals in the puzzle must contain one occurrence of each 1-9 digit. The diagonals are marked in the puzzle so you wouldn’t forget about them. Click on the puzzle thumbnail to access the puzzle.
Samarai Sudoku book

Posted in Free sample puzzles, Samurai sudoku | Tagged , , , , | Leave a comment

Double Trouble!

By djape | Published: November 24, 2005
I have just completed a new enhanced version of my puzzle generator. We can now create any kind of overlapping Sudoku puzzles (Samurai-like) – that is, with any number or arrangement of 9×9 classic Sudoku inside. Here I’m posting my first such puzzle – I’m calling it Double Trouble (the puzzle formerly known as “doubled-doku”). To spice it up a little extra, I made it “X” so be careful about the diagonals! Click on the puzzle thumbnail to access the puzzle.
Flower Sudoku, Gattai 5 in 1 Su Doku

Comments, suggestions?
Posted in Free sample puzzles, Sudoku Variants | Tagged , , , , | 5 Responses

We’re going to Greece!

By djape | Published: November 22, 2005
Another proud announcement – Compupress, a publishing company from Athens, Greece, will start printing our puzzles in their magazines in December issues of their bi-weekly and monthly magazines. The puzzles will include all of the following: Sudoku X, Samurai and of course Killer Sudoku. They will be printing our puzzles every month. If you are interested in publishing our puzzles in your newspaper/magazine, just drop a note to us.
Posted in Killer Sudoku, Puzzle books | Tagged , , , | Leave a comment

More Swordfish

By djape | Published: November 22, 2005
I posted another classic Sudoku that requires Swordfish/X-Wing solving technique. You should practice this technique because at some stage I might post a Killer Sudoku that will require you to use this technique to solve the puzzle. Maybe. 🙂 Of course I also posted another Killer – it’s a Brain X. Have fun.
Posted in Killer Sudoku | Tagged , , , , , , , , | 2 Responses

Perfect Books in bookshops!

By djape | Published: November 20, 2005
It is with great pleasure that I announce that two books with Perfect Sudoku puzzles have been printed and will reach bookshops very soon. I have hinted this before but it’s now official. Both books will be available in bookshops in Portugal only, thanks to Via Optima publishing house from Portugal. They will appear there in about one week but no later than Friday, November 25. The first book is called Sudoku K and it contains 101 Killer Sudoku puzzles created by Perfect Sudoku software and with all levels of difficulty. Here is the cover page for this book:
Sudoku K
The second book is called The Lord of the Sudokus and it is a collection of 365 sequential Sudokus plus 1 bonus puzzle about which I’m not going to reveal too much. The sequential puzzles are just like the ones that I posted a few days ago – in case you haven’t tried them you can have another look. There is also a story that goes along with the puzzles. This is the book cover:
The Lorf od the Sudokus
We are working on making these books available to people from other countries too. They will be released in PDF form and sold through this website. More details about that in the coming days.
Posted in Killer Sudoku, Puzzle books | Tagged , , , , , , | 12 Responses

Perfect Samurai puzzles in Washington Express

By djape | Published: November 20, 2005
I have another announcement to make – as of tomorrow – Friday, November 18, our Samurai puzzles will be published every Friday in Washington Express a free daily commuter newspaper that is published in Washington D.C.. It is highly likely that there will also be Killer Sudokus published in the same paper very soon So if you live or work in that area, look for your free copy of Washington Express around your metro station!
Posted in Killer Sudoku, Puzzle books, Samurai sudoku, Washington Post | Tagged , , , , , | 8 Responses

Weekly Samurai X

By djape | Published: November 19, 2005
Samurai X for Saturday, November 19 – this is the only place you can find these kind of Sudoku puzzles! Basically, not only do you have to fight against 5 interconnected Sudokus, but you also need to be carefull about the diagonals: ALL diagonals in the puzzle must contain one occurrence of each 1-9 digit. The diagonals are marked in the puzzle so you wouldn’t forget about them. Click on the puzzle thumbnail to access the puzzle.
Super Sudoku Quad Samurai Puzzle Book with Variants

Posted in Free sample puzzles, Samurai sudoku | Tagged , | 1 Response

X-Wing

By djape | Published: November 15, 2005
UPDATE: I changed the image to reflect an actual X-Wing. As a matter of fact, this is the puzzle that I posted a couple of days ago under the “daily Sudoku” page. Here is a quick explanation for the “X-Wing” technique. Suppose you reach the following position and you can’t go any further:
X-Wing
Djape does Sudoku

You look at columns 4 and 7 and you search for cells where digit 1 is a candidate. You find that only R4C4, R4C7, R8C4 and R8C7 have 1 as a candidate. So all 4 of those cells that belong to columns 4 and 7 (2 different columns) belong to 2 different rows (4 and 8 ). Now, digit 1 must be somewhere in both columns 4 and 7 – but if it must be in rows 4 and 8 then digit 1 can be erased from rows 4 and 8 except of course from R4C4, R4C7, R8C4 and R8C7. So, this technique doesn’t solve a cell. It only eliminates candidates from some cells, which could help you solve the puzzle. But in this case, it indirectly solves R4C9=9 (you eliminate 1 from there). That was X-Wing. Swordfish is a more complex version. Basically, you’re looking for any number of columns (let’s say “n” columns) that can have your chosen digit in up to “n” different rows. Then you can erase that chosen digit from other cells in those rows.
I’m terrible at explaining things. This only proves it. 🙂 lol
Posted in Solving tips | Tagged , , , , , | 29 Responses

Swordfish

By djape | Published: November 14, 2005
As promised, I implemented the Swordfish classic Sudoku solving technique in my Perfect Sudoku software and generated a few puzzles. I just posted one of them on the Daily Sudoku page. However, I ran my generator and generated a couple of thousands Killer Sudokus and NONE of them required Swordfish, just as I speculated before. Surely, in some of them you could use Swordfish, but they could also be solved by other Killer and/or classic Sudoku techniques. I will keep trying to generate one that REQUIRE Swordfish and will post it if I get it. By the way, I consider X-Wing to be a simplified version of Swordfish, so everything I just said applies to X-Wing too. Let me know how you like this “fiendish” classic Sudoku puzzles…
Posted in Killer Sudoku, Solving tips | Tagged , , , , , , , , , , , | 8 Responses

Weekend Special – Insane Killer

By djape | Published: November 12, 2005
Ok thanks for all your comments to my post regarding the difficulty of some puzzles. I completely changed the rating system and created a large number of puzzles just to test it. As promised – I just posted an extra killer puzzle, rated (by the new rating system) as INSANE. It’s actually one of the puzzles with the highest overall difficulty rating – I hope you find this one challenging. If not – well, I’ll have to redo the rating again :). Let me know how you feel about this one… Have a good weekend!
Posted in General | Tagged , , | 7 Responses
eXTReMe Tracker