What is a fin in Sudoku?

These +8 cells are the 'fin'. The 'fin' or 'fillet' rule goes as follows: If you can form an X-Wing by ignoring the fin cells, then you can keep your elimination of any cell that shares the same unit as all the cells in the fin. It's important to remember we can only have one fin at a time!

What is finned fish in Sudoku?

A finned N-fish with elimination * for a given digit d is a set of N rows together with a cell * not in one of these rows, such that, after removal of all cells that 'see' * (i.e., lie in the same row, column or box as *), the remaining cells in these N rows that have d as a candidate lie in N-1 columns.

How do you identify Swordfish pattern in Sudoku?

A Swordfish is a 3 by 3 nine-cell pattern where a candidate is found on three different rows (or three columns) and they line up in the opposite direction.

What is sashimi in Sudoku?

The Sashimi pattern is very similar to the traditional Sudoku X-Wing configuration. In this case, the player also finds one digit with only two possible solutions within two rows/columns. Yet, one of the cells is not connected to another by row or column.

Can you solve hard Sudoku without guessing?

The short answer is yes. Every proper Sudoku puzzle can be solved without ever having to make a guess. Another way of thinking about it is that every Sudoku puzzle can be solved logically. Even though it may require highly complicated solving techniques you're not familiar with.

The finned Xwing. Tutorial #54 Using rows.

How do you solve Sudoku techniques?

The most basic strategy to solve a Sudoku puzzle is to first write down, in each empty cell, all possible entries that will not contradict the One Rule with respect to the given cells. If a cell ends up having only one possible entry, it is a "forced" entry that you should fill in.

What is the rule of 3 in Sudoku?

"Hidden triples" applies when three cells in a row, column, or 3x3 block contain the same three Notes. These three cells also contain other candidates, which may be removed from them.

Is Sudoku good for the brain?

Sudoku keeps your brain active and reduces the risk of Alzheimer's, a most common cause of dementia that affects a person's thinking and behavioural skills. Stimulates your mind: The game works on your logical thinking process as you are absorbed in solving a puzzle and eventually improve your number skills.

What is the 45 rule in Sudoku?

The 45 rule is a basic solving-technique in Killer Sudoku. Each house (row, column, nonet) must add to 45 (the sum of the digits 1 through 9).

Is there a solution to every Sudoku puzzle?

Realistically, no! There are 6,670,903,752,021,072,936,960 possible solvable Sudoku grids that yield a unique result (that's 6 sextillion, 670 quintillion, 903 quadrillion, 752 trillion, 21 billion, 72 million, 936 thousand, 960 in case you were wondering). That's way more than the number of stars in the universe.

How long does it take the average person to solve a hard Sudoku puzzle?

The average person takes more than a few minutes to solve a Sudoku. It requires patience, time, and attention. If you're not very patient by nature, you will likely find yourself very disappointed and annoyed with the game.

What does a colon mean in Sudoku?

The challenge was to fill in the above snake with the digits 1 to 9, using each digit only once. The colon “:” means divide, and you must follow the standard order of operations, meaning that multiplication/division comes before addition/subtraction.

What is the red dot in Sudoku?

The central column (in green) has only two spaces left, and they must contain a 2 and a 6. In the center-right square, there is a 6 (circled in red) which shows us that we can eliminate 6 as being in the top empty space of the column – so that space must contain 2 (marked in blue).

What is the hardest Sudoku game?

Expert Sudoku is a game for experienced Sudoku players with a very high level of difficulty. This hardest Sudoku puzzle is characterized by the fact that only a few numbers are shown in the Sudoku square, which consists of 9 small squares, where the cells are located 3x3.

What is the most clues in Sudoku?

An ordinary puzzle with a unique solution must have at least 17 clues, but this is not mathematically proven. There is a solvable puzzle with at most 21 clues for every solved grid, with the largest minimal puzzle found so far has 40 clues in the 81 cells.

How do you spot a jellyfish in Sudoku?

A Jellyfish occurs when in four rows all possible cells for a given digit lie in four columns. This digit can be eliminated from the remaining cells of these columns.

What is the unique rectangle rule in Sudoku?

A "Unique Rectangle" (UR) consists of four cells that occupy exactly two rows, two columns, and two boxes. All four cells have the same two candidates left (in real sudokus not all cells have to hold all of the UR candidates, see below).

What is chaining in sudoku?

A 'chain' is a series of links hopping from one candidate to another following very simple rules. A candidate can either be ON or OFF. That is, we either think it is a possible solution to that cell, or we do not. There are consequences to the rest of the board when we 'link' these two states.

What does the Japanese word sudoku mean in English?

The name “sudoku” is abbreviated from the Japanese suuji wa dokushin ni kagiru, which means “the numbers (or digits) must remain single.” Now there are sudoku competitions across the globe, and variations of the puzzle often appear side-by-side the crossword puzzle in newspapers and magazines.

What is Sudoku rule of 1?

Rule 1 - Each row must contain the numbers from 1 to 9, without repetitions. The player must focus on filling each row of the grid while ensuring there are no duplicated numbers. The placement order of the digits is irrelevant. Every puzzle, regardless of the difficulty level, begins with allocated numbers on the grid.

What is the one rule in Sudoku?

Sudoku Rule № 1: Use Numbers 1-9

Within the rows and columns are 9 “squares” (made up of 3 x 3 spaces). Each row, column and square (9 spaces each) needs to be filled out with the numbers 1-9, without repeating any numbers within the row, column or square.

Is 6 minutes good for Sudoku?

5 minutes is more than enough time to jump start your brain, re-evaluate your Sudoku strategy, and develop a new perspective on how to view the Sudoku grid. So “take 5” and give yourself a new chance at solving Sudoku puzzles!

Do Sudoku players have high IQ?

From this case study it can be concluded that an individual who is skilled at solving Sudoku puzzles likely has a high general IQ. The results of the weak correlation between Sudoku scores and the WAIT test indicates that in some cases a high Sudoku doesn't necessarily mean a high general IQ.

What kind of person is good at Sudoku?

Orderly, Methodical Mind

The best Sudoku players know how to cut through the visual clutter of a Sudoku grid and start scanning immediately for the most valuable clues and information that they need – they know how to apply a process to the Sudoku grid where they can see which places are the most promising.

Does Sudoku fight dementia?

“Just sitting down and doing Sudoku isn't probably going to be the one key thing that's going to prevent you from developing Alzheimer's disease,” she said. Moreover, doing only one type of puzzle or another is not the key either. The brain needs to be exercised, just like any other muscle in the body.