Chessboard Problems 1 Introduction 2 Knight Problems

Total Page:16

File Type:pdf, Size:1020Kb

Chessboard Problems 1 Introduction 2 Knight Problems Chessboard Problems ExoticArithmetic III 1 Introduction We begin with some definitions. A set of chess pieces is called independent if none of them attack any of the others. A set of pieces covers a board if among them they occupy or threaten each square. Let us denote the squares of an 8 × 8 board using matrix notation. a11 a12 a13 a14 a15 a16 a17 a18 a21 a22 a23 a24 a25 a26 a27 a28 a31 a32 a33 a34 a35 a36 a37 a38 a41 a42 a43 a44 a45 a46 a47 a48 a51 a52 a53 a54 a55 a56 a57 a58 a61 a62 a63 a64 a65 a66 a67 a68 a71 a72 a73 a74 a75 a76 a77 a78 a81 a82 a83 a84 a85 a86 a87 a88 2 Knight Problems Knight problems come in many types. There are two types of domination problems and two types of independence problems and they occur on finite rectangular boards, often 4 × 4 or 8 × 8. These are counting problems and probability problems. We offer two examples. A set of chess knights is called independent if none of them attack any of the others. 1. How many ways can 8 independent knights be placed on an 4 × 4 chess board? To facilitate the solutions and to offer a modest hint, we num- ber the squares of the 4 × 4 board so the odd numbers squares are white and the even ones dark. The second figure shows the number of squares attacked by a knight on the square. 1 Chessboard Problems ExoticArithmetic III 1 2 3 4 2 3 3 2 8 7 6 5 3 4 4 3 9 10 11 12 3 4 4 3 16 15 14 13 2 3 3 2 2. How many ways can 7 independent knights be placed on an 4 × 4 chess board? 3. How many ways can 6 independent knights be placed on an 4 × 4 chess board? 4. Prove that nine knights cannot be arranged independently on a 4 × 4 chess board. 5. Three knights are randomly placed on a 4 × 4 chessboard. What is the probability that none attack the others? 6. Note that a knight move from a position (i; j) to a position (u; v) in the plane, can be characterized by the equation ji − uj · jj − vj = 2. Equivalently, we can say (u − i)2 + (v − j)2 = 5. We can use the notation (i; j)N(u; v) if and only if ji − uj · jj − vj = 2 used in discussion binary relations. (a) Characterize bishop moves using matrix notation. (b) Characterize rook moves using matrix notation. (c) Characterize king moves using matrix notation. 7. (a) Find the maximum number of independent rooks, and the number of ways to arrange them on a board. (If no mention is made of the board's size, assume it is 8 × 8.) (b) Answer the same two questions for bishops. (c) Answer the same two questions for knights. (d) Answer the same two questions for kings. 8. Another important type question regards the number of paths of a knight or a king from one square to another. Now suppose the king 2 Chessboard Problems ExoticArithmetic III is unrestricted. Now our piece is a chess king in the plane. We ask questions like how many paths of length 6 are there that start and end at the origin? We give two alternate solutions. Here is one of my favorites. 9. How many locations can a knight occupy after 10 moves if it starts at the origin on the plane. 10. (a) Find the minimum number of rooks required to cover a board, and the number of ways to arrange them on a board. (b) Answer the same two questions for bishops. (c) Answer the same two questions for knights. (d) Answer the same two questions for kings. 11. There are some famous old questions related to knight's tours, covering the board by queens, and maximal sets of independent queens that are not appropriate for this course, but are worth mentioning here: (a) Find all ways to put eight independent queens on a chess board. (b) Find all ways to put n independent queens on an n × n chess board. (c) Find a covering of a chess board by five queens, and count the number of ways to do this. (d) Find a complete recurrent knight's tour. 3 Interchange Problems Our problem here is to interchange the three white knights with the three black knights in as few moves as possible. We do not require the black and white pieces to move alternately. ~ ~ ~ | | | 3 Chessboard Problems ExoticArithmetic III 4 Covering A perfect cover (also called a tiling) of an m by n chess board by tiles (usually dominoes) is an arrangement of so that (a) the entire board is covered, (b) each tile covers a whole number of squares and (c) there is no overlap except along the edges. 12. Count the number of perfect covers of the chess boards listed below: (a) 2 × 1, 2 × 2, 2 × 3, 2 × 4, 2 × 5, and 2 × 6. More generally, let Gn denote the number of tilings of a 2 × n board. Find Gn for n = 1; 2; 3;:::; 10. The five perfect tilings of a 2 × 4 are shown below: (b) 3 × 3, 3 × 4, 3 × 5, and 3 × 6. (c) The 62 square board obtained by removing the opposite ends of one of the diagonals. 13. Generalize the definition of tiling to include solid blocks. Find the number of tilings of a 2 × 2 × 2 block by blocks of size 2 × 1 × 1 14. Is it possible to tile a punctured 8×8 chess board (one with one square removed) using regular triominoes ( )? Does it matter which square is removed? 15. Consider a 2n × 2n punctured board. Show by induction that such a board has a multiple of 3 number of squares. Can such a board be tiled by L-shaped triominoes ? 16. A knight is placed on an infinite chess board at the origin (0; 0). Let K(n) denote the number of positions the knight can occupy after n moves. For example K(1) = 8. Find K(n) as a polynomial function on n. 17. How many ways can four independent chess kings be placed on a 4 × 4 board? 4 Chessboard Problems ExoticArithmetic III 18. How many king's paths of length 5 are there from the square numbered 1 to the square numbered 16? A path on length 5 can visit square 16, leave and then return, for example, 1; 6; 11; 16; 12; 16. How many paths of length 3 are there? Length 4? 19. Probability problems. For each two chess pieces randomly placed on two squares of a chessboard, find the probability that one of the pieces attacks the other. (a) knight and rook. (b) bishop and queen. (c) knight and queen. (d) bishop and rook. 20. From Alex Soifer. Forty-one rooks are placed on a 10 × 10 chessboard. Prove that there is among them an independent set of five. 5.
Recommended publications
  • Bishop and Knight Save the Day: a World Champion's Favorite Studies
    Bishop and Knight Save the Day: A World Champion’s Favorite Studies Sergei Tkachenko Bishop and Knight Save the Day: A World Champion’s Favorite Studies Author: Sergei Tkachenko Translated from the Russian by Ilan Rubin Chess editor: Anastasia Travkina Typesetting by Andrei Elkov (www.elkov.ru) © LLC Elk and Ruby Publishing House, 2019. All rights reserved Cover page drawing by Anna Fokina Illustration Studio (www.fox-artwork.com) Follow us on Twitter: @ilan_ruby www.elkandruby.com ISBN 978-5-6040710-9-0 2 THE BISHOP AND THE KNIGHT HAND IN HAND… The bishop and knight pair often make chess players shudder. Why? Because of the tricky checkmate! Mating with a bishop and knight is far from simple. Indeed, there have been cases when famous players were unable to mate their opponent in the allocated 50 moves. One example involved the Kievan master Evsey Poliak. The game ended in a draw after he failed to mate his opponent with bishop, knight and king versus a lone king. After the game, somebody asked him why he didn’t chase the enemy king into a corner that was the same color as his bishop. The disappointed Poliak replied: “I kept trying to chase him but for some reason the king refused to move there!” There was even an old painting that captured this balance of forces! Back in 1793, French artist Remi-Fursy Descarsin painted a doctor playing chess against… the Grim Reaper, no less. And the doctor looks dead pleased, because he’s just mated Death himself with a bishop and knight! 3 Here’s that position from Descarsin’s painting (No.
    [Show full text]
  • Combinatorics on the Chessboard
    Combinatorics on the Chessboard Interactive game: 1. On regular chessboard a rook is placed on a1 (bottom-left corner). Players A and B take alternating turns by moving the rook upwards or to the right by any distance (no left or down movements allowed). Player A makes the rst move, and the winner is whoever rst reaches h8 (top-right corner). Is there a winning strategy for any of the players? Solution: Player B has a winning strategy by keeping the rook on the diagonal. Knight problems based on invariance principle: A knight on a chessboard has a property that it moves by alternating through black and white squares: if it is on a white square, then after 1 move it will land on a black square, and vice versa. Sometimes this is called the chameleon property of the knight. This is related to invariance principle, and can be used in problems, such as: 2. A knight starts randomly moving from a1, and after n moves returns to a1. Prove that n is even. Solution: Note that a1 is a black square. Based on the chameleon property the knight will be on a white square after odd number of moves, and on a black square after even number of moves. Therefore, it can return to a1 only after even number of moves. 3. Is it possible to move a knight from a1 to h8 by visiting each square on the chessboard exactly once? Solution: Since there are 64 squares on the board, a knight would need 63 moves to get from a1 to h8 by visiting each square exactly once.
    [Show full text]
  • A Package to Print Chessboards
    chessboard: A package to print chessboards Ulrike Fischer November 1, 2020 Contents 1 Changes 1 2 Introduction 2 2.1 Bugs and errors.....................................3 2.2 Requirements......................................4 2.3 Installation........................................4 2.4 Robustness: using \chessboard in moving arguments..............4 2.5 Setting the options...................................5 2.6 Saving optionlists....................................7 2.7 Naming the board....................................8 2.8 Naming areas of the board...............................8 2.9 FEN: Forsyth-Edwards Notation...........................9 2.10 The main parts of the board..............................9 3 Setting the contents of the board 10 3.1 The maximum number of fields........................... 10 1 3.2 Filling with the package skak ............................. 11 3.3 Clearing......................................... 12 3.4 Adding single pieces.................................. 12 3.5 Adding FEN-positions................................. 13 3.6 Saving positions..................................... 15 3.7 Getting the positions of pieces............................ 16 3.8 Using saved and stored games............................ 17 3.9 Restoring the running game.............................. 17 3.10 Changing the input language............................. 18 4 The look of the board 19 4.1 Units for lengths..................................... 19 4.2 Some words about box sizes.............................. 19 4.3 Margins.........................................
    [Show full text]
  • 53Rd WORLD CONGRESS of CHESS COMPOSITION Crete, Greece, 16-23 October 2010
    53rd WORLD CONGRESS OF CHESS COMPOSITION Crete, Greece, 16-23 October 2010 53rd World Congress of Chess Composition 34th World Chess Solving Championship Crete, Greece, 16–23 October 2010 Congress Programme Sat 16.10 Sun 17.10 Mon 18.10 Tue 19.10 Wed 20.10 Thu 21.10 Fri 22.10 Sat 23.10 ICCU Open WCSC WCSC Excursion Registration Closing Morning Solving 1st day 2nd day and Free time Session 09.30 09.30 09.30 free time 09.30 ICCU ICCU ICCU ICCU Opening Sub- Prize Giving Afternoon Session Session Elections Session committees 14.00 15.00 15.00 17.00 Arrival 14.00 Departure Captains' meeting Open Quick Open 18.00 Solving Solving Closing Lectures Fairy Evening "Machine Show Banquet 20.30 Solving Quick Gun" 21.00 19.30 20.30 Composing 21.00 20.30 WCCC 2010 website: http://www.chessfed.gr/wccc2010 CONGRESS PARTICIPANTS Ilham Aliev Azerbaijan Stephen Rothwell Germany Araz Almammadov Azerbaijan Rainer Staudte Germany Ramil Javadov Azerbaijan Axel Steinbrink Germany Agshin Masimov Azerbaijan Boris Tummes Germany Lutfiyar Rustamov Azerbaijan Arno Zude Germany Aleksandr Bulavka Belarus Paul Bancroft Great Britain Liubou Sihnevich Belarus Fiona Crow Great Britain Mikalai Sihnevich Belarus Stewart Crow Great Britain Viktor Zaitsev Belarus David Friedgood Great Britain Eddy van Beers Belgium Isabel Hardie Great Britain Marcel van Herck Belgium Sally Lewis Great Britain Andy Ooms Belgium Tony Lewis Great Britain Luc Palmans Belgium Michael McDowell Great Britain Ward Stoffelen Belgium Colin McNab Great Britain Fadil Abdurahmanović Bosnia-Hercegovina Jonathan
    [Show full text]
  • UIL Text 111212
    UIL Chess Puzzle Solvin g— Fall/Winter District 2016-2017 —Grades 4 and 5 IMPORTANT INSTRUCTIONS: [Test-administrators, please read text in this box aloud.] This is the UIL Chess Puzzle Solving Fall/Winter District Test for grades four and five. There are 20 questions on this test. You have 30 minutes to complete it. All questions are multiple choice. Use the answer sheet to mark your answers. Multiple choice answers pur - posely do not indicate check, checkmate, or e.p. symbols. You will be awarded one point for each correct answer. No deductions will be made for incorrect answers on this test. Finishing early is not rewarded, even to break ties. So use all of your time. Some of the questions may be hard, but all of the puzzles are interesting! Good luck and have fun! If you don’t already know chess notation, reading and referring to the section below on this page will help you. How to read and answer questions on this test Piece Names Each chessman can • To answer the questions on this test, you’ll also be represented need to know how to read chess moves. It’s by a symbol, except for the pawn. simple to do. (Figurine Notation) K King Q • Every square on the board has an “address” Queen R made up of a letter and a number. Rook B Bishop N Knight Pawn a-h (We write the file it’s on.) • To make them easy to read, the questions on this test use the figurine piece symbols on the right, above.
    [Show full text]
  • The Oldest Books on Modern Chess
    The Oldest Books on Modern Chess By Jon Crumiller © 2016 Worldchess.com Nobody expects the Spanish Inquisition. But when players respond to 1. e4 with 1. … e5, they can often be subjected to the Spanish Torture. That’s a well-known nickname for the Ruy López, one of the oldest and most commonly used openings in chess. The nickname is possibly not a coincidence; the Inquisition was active in Spain in 1561, the same year that the Spanish priest named Ruy López de Segura published his celebrated work, Libro de la Invencion liberal y Arte del juego del Axedrez. The book contained the analysis from which the chess opening received its eponymous name. Jonathan Crumiller The passage highlighted above can roughly be translated: White king’s pawn goes to the fourth. If black plays the king’s pawn to the fourth: white plays the king’s knight to the king’s bishop third, over the pawn. If black plays the queen’s knight to queen’s bishop third: white plays the king’s bishop to the fourth square of the contrary queen’s knight, opposed to that knight. Or in our modern chess language: 1. e4, e5 2. Nf3, Nc6 3. Bb5. Jonathan Crumiller On the right is how the Ruy López opening would have looked four centuries ago with a standard chess set and board in Spain. This Spanish chess set is one of my oldest complete sets (along with a companion wooden set of the same era). Jonathan Crumiller Here is the Ruy López as seen with that companion set displayed on a Spanish chessboard, also from the 1600’s.
    [Show full text]
  • Proposal to Encode Heterodox Chess Symbols in the UCS Source: Garth Wallace Status: Individual Contribution Date: 2016-10-25
    Title: Proposal to Encode Heterodox Chess Symbols in the UCS Source: Garth Wallace Status: Individual Contribution Date: 2016-10-25 Introduction The UCS contains symbols for the game of chess in the Miscellaneous Symbols block. These are used in figurine notation, a common variation on algebraic notation in which pieces are represented in running text using the same symbols as are found in diagrams. While the symbols already encoded in Unicode are sufficient for use in the orthodox game, they are insufficient for many chess problems and variant games, which make use of extended sets. 1. Fairy chess problems The presentation of chess positions as puzzles to be solved predates the existence of the modern game, dating back to the mansūbāt composed for shatranj, the Muslim predecessor of chess. In modern chess problems, a position is provided along with a stipulation such as “white to move and mate in two”, and the solver is tasked with finding a move (called a “key”) that satisfies the stipulation regardless of a hypothetical opposing player’s moves in response. These solutions are given in the same notation as lines of play in over-the-board games: typically algebraic notation, using abbreviations for the names of pieces, or figurine algebraic notation. Problem composers have not limited themselves to the materials of the conventional game, but have experimented with different board sizes and geometries, altered rules, goals other than checkmate, and different pieces. Problems that diverge from the standard game comprise a genre called “fairy chess”. Thomas Rayner Dawson, known as the “father of fairy chess”, pop- ularized the genre in the early 20th century.
    [Show full text]
  • Chess-Training-Guide.Pdf
    Q Chess Training Guide K for Teachers and Parents Created by Grandmaster Susan Polgar U.S. Chess Hall of Fame Inductee President and Founder of the Susan Polgar Foundation Director of SPICE (Susan Polgar Institute for Chess Excellence) at Webster University FIDE Senior Chess Trainer 2006 Women’s World Chess Cup Champion Winner of 4 Women’s World Chess Championships The only World Champion in history to win the Triple-Crown (Blitz, Rapid and Classical) 12 Olympic Medals (5 Gold, 4 Silver, 3 Bronze) 3-time US Open Blitz Champion #1 ranked woman player in the United States Ranked #1 in the world at age 15 and in the top 3 for about 25 consecutive years 1st woman in history to qualify for the Men’s World Championship 1st woman in history to earn the Grandmaster title 1st woman in history to coach a Men's Division I team to 7 consecutive Final Four Championships 1st woman in history to coach the #1 ranked Men's Division I team in the nation pnlrqk KQRLNP Get Smart! Play Chess! www.ChessDailyNews.com www.twitter.com/SusanPolgar www.facebook.com/SusanPolgarChess www.instagram.com/SusanPolgarChess www.SusanPolgar.com www.SusanPolgarFoundation.org SPF Chess Training Program for Teachers © Page 1 7/2/2019 Lesson 1 Lesson goals: Excite kids about the fun game of chess Relate the cool history of chess Incorporate chess with education: Learning about India and Persia Incorporate chess with education: Learning about the chess board and its coordinates Who invented chess and why? Talk about India / Persia – connects to Geography Tell the story of “seed”.
    [Show full text]
  • NEW HAMPSHIRE CHESS JOURNAL Is a Publication of the New Hampshire Chess Association
    New Hampshire Chess Journal December 2013 Volume 2013 No. 1 Return of the King: Sharif Khater Story, Page 2 Khater Returns as 2013 NH Amateur Champ Manchester--Sherif Khater recaptured the State Amateur crown, which he first held in 2010, by beating Arthur Tang in the final round of the 38th New Hampshire Amateur Championship, held at the Comfort Inn in Manchester on November 2. Only a second round draw with Brian Bambrough blemished Khater’s score. Four tied for second place: Gerald Potorski, Jefferey Ames, Clay Bradley, and Joshua Cote. John Jay Naylor won the Intermediate section with a perfect 4.0 score. Thomas Allen of Maine scored a perfect 4.0 for first place in the Novice section. Sixty-four players competed in the four round, one day event. Hal Terrie directed with the assistance of John Elmore. The crosstable can be viewed here. Bournival NH Open State Champ Manchester—Brad Bournival was named the 2013 NH State Champion at the 63rd New Hampshire Open. GM Alexander Ivanov and Jonathan Yedidia, both of Massachusetts, shared first place. Yedidia caught Ivanov in the final round by beating Brian Salomon while Ivanov drew with state champ Brad Bournival, leaving the leaders with 4.0 points each. Bournival took third place. John Pythyon, Sr. of Maine won the under 1950 section, while Paul Kolojeski Alexander Ivanov and Brian Salomon square off in Round 4. Ivanov won. 2 prevailed in the Under 1650 section. The Open drew 37 participants to the Manchester Comfort in on June 14-16. The tournament was directed by Hal Terrie with John Elmore assisting.
    [Show full text]
  • Chess Rules Ages 10 & up • for 2 Players
    Front (Head to Head) Prints Pantone 541 Blue Chess Rules Ages 10 & Up • For 2 Players Contents: Game Board, 16 ivory and 16 black Play Pieces Object: To threaten your opponent’s King so it cannot escape. Play Pieces: Set Up: Ivory Play Pieces: Black Play Pieces: Pawn Knight Bishop Rook Queen King Terms: Ranks are the rows of squares that run horizontally on the Game Board and Files are the columns that run vertically. Diagonals run diagonally. Position the Game Board so that the red square is at the bottom right corner for each player. Place the Ivory Play Pieces on the first rank from left to right in order: Rook, Knight, Bishop, Queen, King, Bishop, Knight and Rook. Place all of the Pawns on the second rank. Then place the Black Play Pieces on the board as shown in the diagram. Note: the Ivory Queen will be on a red square and the black Queen will be on a black space. Play: Ivory always plays first. Players alternate turns. Only one Play Piece may be moved on a turn, except when castling (see description on back). All Play Pieces must move in a straight path, except for the Knight. Also, the Knight is the only Play Piece that is allowed to jump over another Play Piece. Play Piece Moves: A Pawn moves forward one square at a time. There are two exceptions to this rule: 1. On a Pawn’s first move, it can move forward one or two squares. 2. When capturing a piece (see description on back), a Pawn moves one square diagonally ahead.
    [Show full text]
  • Reshevsky Wins Playoff, Qualifies for Interzonal Title Match Benko First in Atlantic Open
    RESHEVSKY WINS PLAYOFF, TITLE MATCH As this issue of CHESS LIFE goes to QUALIFIES FOR INTERZONAL press, world champion Mikhail Botvinnik and challenger Tigran Petrosian are pre­ Grandmaster Samuel Reshevsky won the three-way playoff against Larry paring for the start of their match for Evans and William Addison to finish in third place in the United States the chess championship of the world. The contest is scheduled to begin in Moscow Championship and to become the third American to qualify for the next on March 21. Interzonal tournament. Reshevsky beat each of his opponents once, all other Botvinnik, now 51, is seventeen years games in the series being drawn. IIis score was thus 3-1, Evans and Addison older than his latest challenger. He won the title for the first time in 1948 and finishing with 1 %-2lh. has played championship matches against David Bronstein, Vassily Smyslov (three) The games wcre played at the I·lerman Steiner Chess Club in Los Angeles and Mikhail Tal (two). He lost the tiUe to Smyslov and Tal but in each case re­ and prizes were donated by the Piatigorsky Chess Foundation. gained it in a return match. Petrosian became the official chal­ By winning the playoff, Heshevsky joins Bobby Fischer and Arthur Bisguier lenger by winning the Candidates' Tour­ as the third U.S. player to qualify for the next step in the World Championship nament in 1962, ahead of Paul Keres, Ewfim Geller, Bobby Fischer and other cycle ; the InterzonaL The exact date and place for this event havc not yet leading contenders.
    [Show full text]
  • Origins of Chess Protochess, 400 B.C
    Origins of Chess Protochess, 400 B.C. to 400 A.D. by G. Ferlito and A. Sanvito FROM: The Pergamon Chess Monthly September 1990 Volume 55 No. 6 The game of chess, as we know it, emerged in the North West of ancient India around 600 A.D. (1) According to some scholars, the game of chess reached Persia at the time of King Khusrau Nushirwan (531/578 A.D.), though some others suggest a later date around the time of King Khusrau II Parwiz (590/628 A.D.) (2) Reading from the old texts written in Pahlavic, the game was originally known as "chatrang". With the invasion of Persia by the Arabs (634/651 A.D.), the game’s name became "shatranj" because the phonetic sounds of "ch" and "g" do not exist in Arabic language. The game spread towards the Mediterranean coast of Africa with the Islamic wave of military expansion and then crossed over to Europe. However, other alternative routes to some parts of Europe may have been used by other populations who were playing the game. At the moment, this "Indian, Persian, Islamic" theory on the origin of the game is accepted by the majority of scholars, though it is fair to mention here the work of J. Needham and others who suggested that the historical chess of seventh century India was descended from a divinatory game (or ritual) in China. (3) On chess theories, the most exhaustive account founded on deep learning and many years’ studies is the A History of Chess by the English scholar, H.J.R.
    [Show full text]