"7 is not. Like sudoku, the solver must fill the remaining white cells with numbers 1 to 9 (or 1 to n in puzzles with N cells per side) such that each row and column contains unique digits. Whereas Sudoku has the additional constraint of 3x3 ""boxes"", in Str8ts rows and columns are divided by blacks cells. Additional clues are set in some of the black cells – these numbers remove that digit as an option in the row and column. Such digits do not form part of any straight. There are a number of variants to the basic game,"
"3 are dotted in all sequences. There are 18 squares, with each sequence occurring 3 times. The aim of the puzzle is to take 9 squares out of the collection and arrange them in a 3×3 ""medjig-square"" in such a way that each row and column formed by the quadrants sums to 9, along with the two long diagonals. The medjig method of constructing a magic square of order 6 is as follows: Example: Similarly, for any larger integer ""N"", a magic square of order 2""N"" can be constructed from any ""N"" × ""N"" medjig-square with each row, column, and"
"Glossary of Sudoku This is a glossary of Sudoku terms and jargon. It is organized thematically, with links to references and example usage provided as ([1]). Sudoku with a 9×9 grid is assumed, unless otherwise noted. A Sudoku (i.e. the ""puzzle"") is a partially completed grid. A grid has 9 rows, 9 columns and 9 boxes, each having 9 cells (81 total). Boxes can also be called blocks or regions. Horizontally adjacent rows are a band, and vertically adjacent columns are a stack. The initially defined values are clues or givens. An ordinary Sudoku (i.e. a proper Sudoku) has one"
"Navigrid Navigrid is a logic-based number-placement puzzle. The puzzler is provided with a set of movements which must be used to move between the numbers 1 to 9 in order starting with the number 1. A solved grid will contain each of the numbers 1 to 9. The puzzle setter provides a partially completed grid. The puzzle was invented by an English puzzle enthusiast, Laurence May, in 2006 and was first published by BBC MindGames Magazine where it appeared in all 9 issues. It is produced by Vexus Puzzle Design and is currently represented by Puzzler Media. The puzzle appears"
"of either two squares to the left and then one square down or one square down and then two squares to the left. Navigrid Navigrid is a logic-based number-placement puzzle. The puzzler is provided with a set of movements which must be used to move between the numbers 1 to 9 in order starting with the number 1. A solved grid will contain each of the numbers 1 to 9. The puzzle setter provides a partially completed grid. The puzzle was invented by an English puzzle enthusiast, Laurence May, in 2006 and was first published by BBC MindGames Magazine where"
"of these is ""Greater Than Sudoku"". In this, a 3×3 grid of the Sudoku is given with 12 symbols of Greater Than (>) or Less Than (<) on the common line of the two adjacent numbers. Another variant on the logic of solution is ""Clueless Sudoku"", in which nine 9×9 Sudoku grids are each placed in a 3×3 array. The center cell in each 3×3 grid of all nine puzzles is left blank and form a tenth Sudoku puzzle without any cell completed; hence, ""clueless"". Examples and other variants can be found in the Glossary of Sudoku. This section refers"
"run diagonally and even branching. Such mechanics creates entangled patterns resulting in interesting challenges and unusual logic. Strimko challenges were handcrafted by Helen, Tanya, and Peter Grabarchuk, and hundreds of original Strimko puzzles were published in various forms and platforms: Web, iOS, PC/Mac, Kindle, paperback. The goal of the game is to fully fill in the given grid (3x3, 4x4, 5x5 ...) with missing numbers observing three simple rules. Rule #1 Each row must contain different numbers. Rule #2 Each column must contain different numbers. Rule #3 Each stream must contain different numbers. The game was well received and receive"
"solution. Rows, columns and regions can be collectively referred to as groups, of which the grid has 27. The One Rule encapsulates the three prime rules, i.e. each digit (or number) can occur only once in each row, column, and box; and can be compactly stated as: ""Each digit appears once in each group."" The classic 9×9 Sudoku format can be generalized to an This accommodates variants by region size and shape, e.g. 6-cell rectangular regions. (""N""×""N"" Sudoku is square). For prime N, polyomino-shaped regions can be used and the requirement to use equal-sized regions, or have the regions entirely"
"+ e Q is trivially obvious, by symmetry (or can be similarly proved from first principles). </poem> Sujiko Sujiko is a logic-based, combinatorial number-placement puzzle created by Jai Gomer of Kobayaashi Studios. The puzzle takes place on a 3x3 grid with four circled number clues at the centre of each quadrant which indicate the sum of the four numbers in that quadrant. The numbers 1-9 must be placed in the grid, in accordance with the circled clues, to complete the puzzle. Sujiko is featured in UK newspapers including ""The Times"", ""The Telegraph"", and ""The Sun"". The puzzle has a mathematical"
"Sujiko Sujiko is a logic-based, combinatorial number-placement puzzle created by Jai Gomer of Kobayaashi Studios. The puzzle takes place on a 3x3 grid with four circled number clues at the centre of each quadrant which indicate the sum of the four numbers in that quadrant. The numbers 1-9 must be placed in the grid, in accordance with the circled clues, to complete the puzzle. Sujiko is featured in UK newspapers including ""The Times"", ""The Telegraph"", and ""The Sun"". The puzzle has a mathematical property, often ignored by puzzle setters, that can sometimes make supposedly-difficult examples somewhat trivial, as follows: The"
"Nine-Colour Cube The Nine-Colour Cube (""see below"" for other names) is a cubic twisty puzzle. It was invented in 2005 by Milan Vodicka and mass-produced by Meffert's seven years later. Mechanically, the puzzle is identical to the Rubik's Cube; however, unlike the Rubik's Cube, which only has 6 different colours, the Nine-Colour Cube has 9 colours, with the individual pieces having one colour each. The puzzle is known under several different names. Milan Vodicka, the inventor, initially gave it the name ""Nine-Colour Scramble Cube"", which reflected the key feature and the ""de facto"" objective of the puzzle. This name was"
"difficulty levels. In August 2010, a wooden board and piece version was designed by Intellego holzspiele. Widderich appeared with the game in the fifth season of the Canadian television show ""Dragons' Den"" on November 24, 2010, where he made a deal for a $150,000 investment in return for 10% royalties, from three of the panelists. The solver is given a 9x9 grid, partially divided by black cells into ""compartments"". Each compartment, vertically or horizontally, must contain a ""straight"" – a set of consecutive numbers, but in any order. For example: 7, 6, 4, 5 is valid, but 1, 3, 8,"
"6,670,903,752,021,072,936,960 , or around . This is roughly times the number of 9×9 Latin squares. Various other grid sizes have also been enumerated—see the main article for details. The number of essentially different solutions, when symmetries such as rotation, reflection, permutation, and relabelling are taken into account, was shown to be just 5,472,730,538 . Unlike the number of complete Sudoku grids, the number of minimal 9×9 Sudoku puzzles is not precisely known. (A minimal puzzle is one in which no clue can be deleted without losing uniqueness of the solution.) However, statistical techniques combined with a puzzle generator show that"
"of a second. A puzzle can be expressed as a graph coloring problem. The aim is to construct a 9-coloring of a particular graph, given a partial 9-coloring. The graph has 81 vertices, one vertex for each cell. The vertices are labeled with ordered pairs (""x"", ""y""), where ""x"" and ""y"" are integers between 1 and 9. In this case, two distinct vertices labeled by (""x"", ""y"") and (""x""′, ""y""′) are joined by an edge if and only if: The puzzle is then completed by assigning an integer between 1 and 9 to each vertex, in such a way that"
"of 1-12 (3×4=12) to their places so that the sums are correct. The puzzle has a unique solution found stepwise as follows: The missing numbers are 1,2,4,5,7,9,10,11,12. Usually it is best to start from a row or a column with fewest missing numbers. In this case columns A, B, and C are such. Column A is not favorable since the sum 19 of missing numbers can be presented according to the rules in several ways (e.g. 19 = 7 + 12 = 12 + 7 = 9 + 10 = 10 + 9). In the column B the sum of"
"Izukirudo Izukirudo, is a French logic puzzle and a word puzzle on grid created in 2006 and inspired by Picross. The name Izukirudo is the pronunciation of the name of its creator (Franck Izquierdo) in Japanese. The goal is to find all the right boxes to circle in each grid. For this, numerical indices are placed above and to the left of the grid. These indices show the order and group size of the boxes to circle, where a group consists of circled letters adjacent to each other. For example, 3, 1 written on the left axis indicates, left to"
"6 for a 6×6, etc. –– so that no digit appears more than once in any row or any column (a Latin square). Grids range in size from 3×3 to 9×9. Additionally, KenKen grids are divided into heavily outlined groups of cells –– often called “cages” –– and the numbers in the cells of each cage must produce a certain “target” number when combined using a specified mathematical operation (one of addition, subtraction, multiplication or division). For example, a linear three-cell cage specifying addition and a target number of 6 in a 4×4 puzzle must be satisfied with the digits"
"about (with 0.065% relative error) 3.10 × 10 minimal puzzles and 2.55 × 10 nonessentially equivalent minimal puzzles exist. Sudoku Completed games are always a type of Latin square with an additional constraint on the contents of individual regions. For example, the same single integer may not appear twice in the same row, column, or any of the nine 3×3 subregions of the 9x9 playing board. French newspapers featured variations of the puzzles in the 19th century, and the puzzle has appeared since 1979 in puzzle books under the name Number Place. However, the modern Sudoku only started to become"
"Nine Holes Nine Holes is a two-player abstract strategy game from different parts of the world and is centuries old. It was very popular in England. It is related to tic-tac-toe, but even more related to Three Men's Morris, Achi, Tant Fant, Shisima, Picaria, and Dara, because pieces are moved on the board to create the 3 in-a-row. It is an alignment game. To create a 3 in-a-row of one's pieces either horizontally or vertically. Diagonals do not count. A 3 x 3 peg board is preferable. Each player has 3 pieces. One plays the black pieces, and the other"
"same number. On July 6, 1895, ""Le Siècle"" rival, ""La France"", refined the puzzle so that it was almost a modern Sudoku. It simplified the 9×9 magic square puzzle so that each row, column, and broken diagonals contained only the numbers 1–9, but did not mark the subsquares. Although they are unmarked, each 3×3 subsquare does indeed comprise the numbers 1–9 and the additional constraint on the broken diagonals leads to only one solution. These weekly puzzles were a feature of French newspapers such as ""L'Echo de Paris"" for about a decade, but disappeared about the time of World War"
"along with Sudoku and Kakuro in their ""Kakuro"" magazine. When the grid is completed, it must be possible to use every one of the 8 movements to journey from the number 1 to the number 2, from the number 2 to the number 3 and so on until you can move from the number 8 to the number 9. A movement must not take you through a black square. Both parts of a movement must be used but they can be used in either order. Example movements are shown in the first image above. The first movement represents a move"
"Sudoku solving algorithms A standard Sudoku contains 81 cells, in a 9×9 grid, and has 9 boxes, each box being the intersection of the first, middle, or last 3 rows, and the first, middle, or last 3 columns. Each cell may contain a number from one to nine, and each number can only occur once in each row, column, and box. A Sudoku starts with some cells containing numbers (""clues""), and the goal is to solve the remaining cells. Proper Sudokus have one solution. Players and investigators may use a wide range of computer algorithms to solve Sudokus, study their"
"to classic Sudoku, disregarding jigsaw, hyper, and other variants. A completed Sudoku grid is a special type of Latin square with the additional property of no repeated values in any of the nine blocks (or ""boxes"" of 3×3 cells). The relationship between the two theories is known, after it was proven that a first-order formula that does not mention blocks is valid for Sudoku if and only if it is valid for Latin squares. The general problem of solving Sudoku puzzles on ""n""×""n"" grids of ""n""×""n"" blocks is known to be NP-complete. Many computer algorithms, such as backtracking and dancing"
"II, III, IV, ..., IX) proposed by ""Hebdomada aenigmatum"", a monthly magazine of Latin puzzles and crosswords. Like the Wordoku, it presents no functional difference from a normal Sudoku, but adds the visual difficulty of using Roman numerals. Hyper Sudoku uses the classic 9×9 grid with 3×3 regions, but defines four additional interior 3×3 regions in which the numbers 1–9 must appear exactly once. It was invented by ""Peter Ritmeester"" and first published by him in Dutch Newspaper ""NRC Handelsblad"" in October 2005, and since April 2007 on a daily basis in ""The International New York Times"" (International Herald Tribune)."
"Nonogram Nonograms, also known as Picross or Griddlers, are picture logic puzzles in which cells in a grid must be colored or left blank according to numbers at the side of the grid to reveal a hidden picture. In this puzzle type, the numbers are a form of discrete tomography that measures how many unbroken lines of filled-in squares there are in any given row or column. For example, a clue of ""4 8 3"" would mean there are sets of four, eight, and three filled squares, in that order, with at least one blank square between successive groups. These"
"to the pattern of even and odd numbers in the 3×3 magic square appears in the ""I Ching"", the first unequivocal instance of this magic square appears in a 1st century book ""Da Dai Liji"" (Record of Rites by the Elder Dai). The above magic squares of orders 3 to 9 are taken from Yang Hui's treatise, in which the Luo Shu principle is clearly evident. The order 5 square is a bordered magic square, with central 3×3 square formed according to Luo Shu principle. The order 9 square is a composite magic square, in which the nine 3×3 sub"
"(i.e., is hit by) exactly one selected possibility. In the standard 9×9 Sudoku variant, there are four kinds of constraints sets corresponding to the four kinds of constraints: Since there are 9 rows, 9 columns, 9 boxes and 9 numbers, there are 9×9=81 row-column constraint sets, 9×9=81 row-number constraint sets, 9×9=81 column-number constraint sets, and 9×9=81 box-number constraint sets: 81+81+81+81=324 constraint sets in all. In brief, the standard 9×9 Sudoku variant is an exact hitting set problem with 729 possibilities and 324 constraint sets. Thus the problem can be represented by a 729×324 matrix. Although it is difficult to present"
"after each individual grid has at least been partially solved. Puzzles constructed from more than two grids are also common. Five 9×9 grids that overlap at the corner regions in the shape of a ""quincunx"" is known in Japan as ""Gattai"" 5 (five merged) Sudoku. In ""The Times"", ""The Age"", and ""The Sydney Morning Herald"", this form of puzzle is known as Samurai SuDoku. ""The Baltimore Sun"" and the ""Toronto Star"" publish a puzzle of this variant (titled High Five) in their Sunday edition. Often, no givens are placed in the overlapping regions. Sequential grids, as opposed to overlapping, are"
"round, the contestant/team must successfully trace out three paths on grids within 90 seconds. The first path is 6 squares (5 squares on a season 1 episode) on a 4x4 grid, the second is 8 squares (10 squares on two season 1 episodes and 9 squares on a season 2 episode) on a 5x5 grid, and the third is 10 squares on a 6x6 grid; squares are always connected (horizontally, vertically, or diagonally). Each square has an actuator in the middle that must be stepped on to activate the square. Contestants see each path twice; the clock starts running when"
"is the length of the grid's edge) such that: A usual place to start are single-celled boxes, as these can be filled in trivially. Then, one can look at boxes that have only one combination of numbers that multiply to make the total. These are often prime-numbered boxes, but can also be, for example, a 2-cell 72, which must contain 8 and 9. The ""naked pairs"" and ""hidden pairs"" techniques, often used in Sudoku, can be applied here. One technique relies on the fact that the product of every row and column is a fixed number. For example, in a"
"on a square grid) published by Nikoli. Atsumari Atsumari (; translates as ""collection"", ""meeting"", or ""cluster"") is a binary-determination puzzle that was originally developed by Quadratic Games for the iPhone platform. The puzzle is played on a hexagonal grid. A rectangular board shape is standard but variations to the board shape can be part of the puzzle design. The puzzle starts with a subset of the hexagonal cells containing a number greater than or equal to zero. The solution to the puzzle is a unique pattern of black/white hexagonal cells that does not violate any of the puzzle rules. ""Atsumari"""
"and sold more than 8 million copies worldwide. Due to its popularity, Nintendo made a second ""Brain Age"" game titled ""Brain Age"", which has over 100 new Sudoku puzzles and other activities. In June 2008, an Australian drugs-related jury trial costing over A$ 1 million was aborted when it was discovered that five of the twelve jurors had been playing Sudoku instead of listening to evidence. Although the 9×9 grid with 3×3 regions is by far the most common, many other variations exist. Sample puzzles can be 4×4 grids with 2×2 regions; 5×5 grids with ""pentomino"" regions have been published"
"Keisuke (puzzle) Keisuke is a logic puzzle published by Nikoli. ""Keisuke"" is played on a rectangular grid, in which some cells of the grid are shaded. Additionally, external to the grid, several numeric values are given, some denoted as horizontal, and some denoted as vertical. The puzzle functions as a simple numeric crossword puzzle. The object is to fill in the empty cells with single digits, such that the given numeric values appear on the grid in the orientation specified. ACROSS → 13, 23, 233, 3221, 21222 DOWN ↓ 12, 21, 22, 232, 3132, 33313 The best way to start"