Questions tagged [sudoku]

A Sudoku is a puzzle consisting of a grid to be filled with symbols, such that each constraining unit contains each symbol exactly once. The typical example is a 9x9 square to be filled with the numbers 1 to 9, where the constraining units are rows, columns, and 3x3 blocks.

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8
votes
2answers
176 views

Double sudoku - two-digit numbers, the 1s and 10s places both form Sudokus [closed]

Using distinct 2-digit numbers from 11-99 that have no zeros, fill in the grid so that the tens digits form a Sudoku and the units digits form a (different) Sudoku. There might be a mathematical way ...
19
votes
1answer
304 views

Escape from Sudoku!

An entry in Fortnightly Topic Challenge #50: Escape Rooms I hesitated to enter this in the Escape Room FTC, but I definitely was inspired by the challenge to create this puzzle, and it is, in some ...
5
votes
1answer
199 views

Chessdoku Level 1 (beginner)

I just tested out a new type of puzzle here (sorry if there's any confusion with the titling) called Chessdoku! Welcome to level 1. Here's the grid: Your goal is to get one black and one white piece ...
12
votes
1answer
383 views

Chessdoku Level 0 (trial)

Welcome to Chessdoku! It's like Sudoku but chess! This is level 0, so it's a trial run and will be fairly simple to solve (level 1 has been posted here). This puzzle is just for the concept. Here you ...
8
votes
1answer
355 views

Trivia… sudoku

An entry in Fortnightly Topic Challenge #49: Pub Quiz Camouflage Please do not search the answers online (hence the no-computers tag), otherwise it would be too simple to solve this puzzle. I tried ...
3
votes
3answers
179 views

Checking for cheating in a Sudoku puzzle?

This may be a question for a Maths forum, but was wondering if anyone has ever seen something that may guide me to a solution. I am writing a Puzzling Site at the moment, which will naturally include ...
8
votes
1answer
695 views

Wanted: Sudoku data in CSV

I am a computer science student looking for unsolved sudoku games that are valid and available in a comma separated text file. Does such a prepared data set exist and where can I find such a data set? ...
14
votes
1answer
445 views

Pento-Doku: Pentominous + Sudoku

Intended for Fortnightly Topic Challenge #47: Wacky Sudokus, but I was too slow making it... not for lack of trying, I assure you This puzzle is both* a Pentominous and a Sudoku**. Rules Solve the ...
3
votes
1answer
87 views

A Final Digitial Sudoku! - SS#14

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the final puzzle in this series! For more information about the series, see the first ...
15
votes
1answer
436 views

This Sudoku Park iS LIT!

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" The grid below is a normal Sudoku grid with normal Sudoku clues, but the completed grid also houses a Statue Park! The completed ...
12
votes
1answer
290 views

Sudoku: Odd Bonds

An entry in Fortnightly Topic Challenge #47: Wacky Sudokus. Edit: Clarified three of the rules. Rules: Normal sudoku rules apply. Inside the sudoku, there exists one "loop". The loop ...
9
votes
1answer
234 views

A Fractal Sudoku - SS#13

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the penultimate puzzle in this series! For more information about the series, see the ...
9
votes
1answer
456 views

Sudoku with no grid and no numbers!!? - SS#12

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the twelfth puzzle in this series! For more information about the series, see the first ...
20
votes
1answer
957 views

Sudoku in Technicolor!

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" This puzzle consists of three overlapping Sudokus, coloured red, blue and green, so each cell will contain three digits, one of ...
-1
votes
1answer
101 views

10X10 Sudoku with a specific requirement

Let's have a 10x10 grid. We want to create a Sudoku in which, in each row, the pairs (a+b), (c+d), (e+f), (g+h), (i+j) add to one of the following numbers: 7, 9, 11, 13, or 15. Can you construct a ...
7
votes
1answer
102 views

This Sudoku takes a step up! - SS#11

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the eleventh puzzle in this series! For more information about the series, see the first ...
37
votes
1answer
1k views

Didn't you ask me for a crossword?

An entry in Fortnightly Topic Challenge #forty-seven: "Wacky Sudokus" Here's that crossword you asked for... Sorry, what's that - you didn't ask me for a crossword?? TASK: Solve the puzzle ...
12
votes
1answer
401 views

Skyscrapers in Sudoku!!! - SS#10

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the tenth puzzle in this series! For more information about the series, see the first ...
26
votes
1answer
1k views

A Puzzling Sudoku (Warning: Hot!)

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" A Sudoku with an oddly familiar shape. Here's a Penpa Link. Rules: Normal Sudoku rules apply (Special) Thermometers: The ...
9
votes
1answer
306 views

A 7x7 Suguru - SS#9

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the ninth puzzle in this series! For more information about the series, see the first ...
25
votes
1answer
1k views

The Blank Sudoku

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" (h/t to Beastly Gerbil, whose 1,2,3... Trinary!!! puzzle provided inspiration for this puzzle) This puzzle is a normal Sudoku, ...
11
votes
1answer
476 views

A Difficult Wacky Sudoku - SS#8

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the eighth puzzle in this series! For more information about the series, see the first ...
12
votes
1answer
242 views

A Scrumptious Sudoku Sandwich - SS#7

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the seventh puzzle in this series! For more information about the series, see the first ...
11
votes
1answer
286 views

Sudoku… with 10 digits? SS#6

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the sixth puzzle in this series! For more information about the series, see the first ...
18
votes
1answer
269 views

Compoundoku wants REALLY BIG and WACKY!

This is an entry for Fortnightly Topic Challenge #47: Wacky Sudokus. Rules of Compoundoku: Solve both left and right Sudokus. In addition, the board below them is the Compound Board of both Sudokus. ...
7
votes
1answer
167 views

A Mosaic Sudoku - SS#5

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the fifth puzzle in this series! For more information about the series, see the first ...
3
votes
1answer
125 views

Sudoku + Nurikabe = Sudokabe

The following Sudoku has a nice little twist: after solving, use the numbers in the green squares as a basis for a Nurikabe puzzle. You can create a new grid for the Nurikabe (a 9x9 grid with the ...
14
votes
1answer
218 views

This is an Odd Sudoku - SS#4

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the fourth puzzle in this series! For more information about the series, see the first ...
9
votes
1answer
156 views

Shattered Webs - SS#3

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the third puzzle in this series! For more information about the series, see the first ...
10
votes
2answers
383 views

1, 2, 3… Trinary!!! (SS#2)

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the second puzzle in this suduko series! For more information about the series, see the ...
14
votes
1answer
583 views

The Blind Killer - a new series! SS#1

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to a new sudoku series! This series will run for the duration of the current Fortnightly ...
12
votes
1answer
736 views

If 2020 Were A Sudoku

A bit of light relief to round out the year. No special genius required :-)
12
votes
2answers
307 views

A sudoku that's already filled in for you

The usual rules of sudoku apply: each row and column must have one of each digit; plus, if you divide the whole nine-by-nine grid into nine three-by-three subgrids, then each subgrid has one of each ...
14
votes
1answer
405 views

Sudoku - less than 6 and knight's move

In the following sudoku, the numbers on the outside indicate the first number less than 6 seen in that row/column. In addition, a number in the sudoku cannot be a knight's move from an identical ...
7
votes
1answer
183 views

The First No L Sudoku

Normal Sudoku rules apply. In addition no L-shaped tetromino can contain four consecutive digits (for instance you can't have r2c9=5,r4c9=8). The little killer clue indicates cells on the indicated ...
11
votes
1answer
272 views

Less than 6 Sudoku

In the following sudoku the numbers on the borders indicate the first number less than 6 seen in that row/column. So for example, the 4 at the bottom means that the first number less than 6 seen from ...
5
votes
1answer
111 views

Sjudoku II - A greater challenge in the world where 9 is 7

This is more difficult instance of a puzzle posted here. Rules similar to Sudoku applies: In each disk, the numbers 1,2,...7 should appear exactly once. No line may contain duplicate digits (note ...
21
votes
2answers
338 views

Tackling The Triptych

Normal Sudoku rules apply. Numbers on thermometers must increase, starting from the bulb end. Killer clues indicate the sum of three digits in a cage, which cannot include repeated digits. In columns ...
36
votes
4answers
2k views

Sjudoku - in a world where 9 is replaced by 7

Sjudoku (sju = seven in Swedish). Rules similar to Sudoku applies: In each disk, the numbers 1,2,...7 should appear exactly once. No line may contain duplicate digits (note that there are lines in 3 ...
11
votes
2answers
552 views

An experimental sudoku

(Here is an experimental Sudoku created by me, however, the "box" constraint is not originally mine, but it'd be fun to try out this constraint.) Rules: Normal Sudoku rules apply. ...
24
votes
3answers
2k views

Ever heard of a W-Sudoku?

You may have heard of a type of Sudoku called an XV-Sudoku. In such a Sudoku, cells connected with an "X" must sum to 10 and cells connected with a "V" must sum to 5. In this W-...
5
votes
1answer
226 views

Sudoku Logic From Another Planet

This is the brutally hard Tatooine Sunset Sudoku puzzle by Philip Newman ... except the Noble Happy Star has goofed! Two of the digits have been swapped and there are multiple solutions. Fortunately, ...
2
votes
1answer
243 views

Suko-kulink (Sudoku, Suko and Slitherlink tri-brid)

Rules: The lower part of the puzzle is a sudoku. Basic sudoku rules applied. The upper and right of the puzzle are suko puzzles. The numbers in circle and to the selected square has the same number ...
6
votes
1answer
110 views

Sudokus everywhere 2

Every 9x9 box is a valid sudoku, making 4 sudokus in all. Hopefully this one is a little more challenging than the previous one. I tried keeping the clues symmetric, but didn't quite manage. Enjoy!
18
votes
1answer
780 views

Sudokus everywhere!

Every 9x9 box is a valid sudoku, making 9 sudokus in all. I'm not sure how hard it is as I started solving it with just a few clues, then added more whenever I got stuck. Enjoy!
6
votes
1answer
1k views

A sudoku with only four given digits and some more rules

Ok so this is one of the hardest sudokus (and one of the best sudoku) I have ever seen, with only $4$ given digits. There are some more rules too :- $(i)$ First, normal sudoku rules apply here. $(ii)$ ...
12
votes
1answer
492 views

An odd looking Sudoku

Somewhat in the spirit of Stiv's This new puzzle type needs a name, can you solve this odd looking Sudoku and give it a name?
8
votes
1answer
291 views

Hero Wars RPG - The Sudoku!

In the popular online action RPG game Hero Wars, the player has to solve some simple but fun puzzles to win loot such as weapons and cash – assuming the incessant ads I’ve seen on Facebook are all ...
1
vote
0answers
143 views

Are there Sudokus that are so hard that no known logical deduction techniques can reduce it? [duplicate]

Are there Sudokus that are so hard that no known logical deduction techniques can reduce it? Maybe such a technique would reduce away multiple options?
3
votes
1answer
217 views

Will forcing chains break this sudoku puzzle?

I am trying to pick up advanced sudoku techniques by practicing with “difficult” puzzles as suggested by my sudoku app. In this puzzle, I am stuck in the position as shown below. I think I can make ...

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