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Four color theorem

Index Four color theorem

In mathematics, the four color theorem, or the four color map theorem, states that no more than four colors are required to color the regions of any map so that no two adjacent regions have the same color. [1]

Table of Contents

  1. 109 relations: Alaska, Alfred Kempe, Angola, Apollonian network, August Ferdinand Möbius, Augustus De Morgan, Azerbaijan, Big O notation, Cabinda Province, Cartography, Compactness theorem, Computational complexity theory, Computer-assisted proof, Connected space, Coq (software), Cubic graph, Cuboid, Cylinder, Daniel P. Sanders, De Bruijn–Erdős theorem (graph theory), Discharging method (discrete mathematics), Discrete Mathematics (journal), Dorothea Blostein, Dror Bar-Natan, Earth–Moon problem, Enclave and exclave, Euler characteristic, Finite type invariant, First-order logic, Five color theorem, Floor and ceiling functions, France, Francis Guthrie, Frederick Guthrie, Genus (mathematics), Georges Gonthier, Gerhard Ringel, Glossary of graph theory, Graph (discrete mathematics), Graph coloring, Graph theory, Grötzsch's theorem, Hadwiger conjecture (graph theory), Hadwiger–Nelson problem, Heawood conjecture, Heinrich Heesch, Heinrich Tietze, Hugo Hadwiger, Immersion (mathematics), John William Theodore Youngs, ... Expand index (59 more) »

  2. Computer-assisted proofs

Alaska

Alaska is a non-contiguous U.S. state on the northwest extremity of North America.

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Alfred Kempe

Sir Alfred Bray Kempe FRS (6 July 1849 – 21 April 1922) was a mathematician best known for his work on linkages and the four colour theorem.

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Angola

Angola, officially the Republic of Angola, is a country on the west-central coast of Southern Africa.

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Apollonian network

In combinatorial mathematics, an Apollonian network is an undirected graph formed by a process of recursively subdividing a triangle into three smaller triangles. Four color theorem and Apollonian network are planar graphs.

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August Ferdinand Möbius

August Ferdinand Möbius (17 November 1790 – 26 September 1868) was a German mathematician and theoretical astronomer.

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Augustus De Morgan

Augustus De Morgan (27 June 1806 – 18 March 1871) was a British mathematician and logician.

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Azerbaijan

Azerbaijan, officially the Republic of Azerbaijan, is a transcontinental country located at the boundary of Eastern Europe and West Asia.

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Big O notation

Big O notation is a mathematical notation that describes the limiting behavior of a function when the argument tends towards a particular value or infinity.

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Cabinda Province

Cabinda (formerly called Portuguese Congo, Kabinda) is an exclave and province of Angola, a status that has been disputed by several political organizations in the territory.

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Cartography

Cartography (from χάρτης chartēs, 'papyrus, sheet of paper, map'; and γράφειν graphein, 'write') is the study and practice of making and using maps.

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Compactness theorem

In mathematical logic, the compactness theorem states that a set of first-order sentences has a model if and only if every finite subset of it has a model.

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Computational complexity theory

In theoretical computer science and mathematics, computational complexity theory focuses on classifying computational problems according to their resource usage, and relating these classes to each other.

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Computer-assisted proof

A computer-assisted proof is a mathematical proof that has been at least partially generated by computer. Four color theorem and computer-assisted proof are computer-assisted proofs.

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Connected space

In topology and related branches of mathematics, a connected space is a topological space that cannot be represented as the union of two or more disjoint non-empty open subsets.

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Coq (software)

Coq is an interactive theorem prover first released in 1989.

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Cubic graph

In the mathematical field of graph theory, a cubic graph is a graph in which all vertices have degree three.

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Cuboid

In geometry, a cuboid is a quadrilateral-faced convex hexahedron, a polyhedron with six faces.

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Cylinder

A cylinder has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes.

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Daniel P. Sanders

Daniel P. Sanders is an American mathematician.

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De Bruijn–Erdős theorem (graph theory)

In graph theory, the De Bruijn–Erdős theorem relates graph coloring of an infinite graph to the same problem on its finite subgraphs. Four color theorem and De Bruijn–Erdős theorem (graph theory) are graph coloring and theorems in graph theory.

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Discharging method (discrete mathematics)

The discharging method is a technique used to prove lemmas in structural graph theory.

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Discrete Mathematics (journal)

Discrete Mathematics is a biweekly peer-reviewed scientific journal in the broad area of discrete mathematics, combinatorics, graph theory, and their applications.

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Dorothea Blostein

Dorothea Blostein (Haken) is a Canadian computer scientist who works as a professor of computer science at Queen's University.

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Dror Bar-Natan

Dror Bar-Natan (דרוֹר בָר-נָתָן; born January 30, 1966) is a professor at the University of Toronto Department of Mathematics, Canada.

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Earth–Moon problem

The Earth–Moon problem is an unsolved problem on graph coloring in mathematics. Four color theorem and Earth–Moon problem are graph coloring.

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Enclave and exclave

An enclave is a territory that is entirely surrounded by the territory of only one other state or entity.

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Euler characteristic

In mathematics, and more specifically in algebraic topology and polyhedral combinatorics, the Euler characteristic (or Euler number, or Euler–Poincaré characteristic) is a topological invariant, a number that describes a topological space's shape or structure regardless of the way it is bent.

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Finite type invariant

In the mathematical theory of knots, a finite type invariant, or Vassiliev invariant (so named after Victor Anatolyevich Vassiliev), is a knot invariant that can be extended (in a precise manner to be described) to an invariant of certain singular knots that vanishes on singular knots with m + 1 singularities and does not vanish on some singular knot with 'm' singularities.

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First-order logic

First-order logic—also called predicate logic, predicate calculus, quantificational logic—is a collection of formal systems used in mathematics, philosophy, linguistics, and computer science.

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Five color theorem

The five color theorem is a result from graph theory that given a plane separated into regions, such as a political map of the countries of the world, the regions may be colored using no more than five colors in such a way that no two adjacent regions receive the same color. Four color theorem and five color theorem are graph coloring and theorems in graph theory.

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Floor and ceiling functions

In mathematics, the floor function is the function that takes as input a real number, and gives as output the greatest integer less than or equal to, denoted or.

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France

France, officially the French Republic, is a country located primarily in Western Europe.

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Francis Guthrie

Francis Guthrie (born 22 January 1831 in London; d. 19 October 1899 in Claremont, Cape Town) was a Cape Colony mathematician and botanist who first posed the Four Colour Problem in 1852.

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Frederick Guthrie

Frederick Guthrie FRS FRSE (15 October 1833 – 21 October 1886) was a British physicist, chemist, and academic author.

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Genus (mathematics)

In mathematics, genus (genera) has a few different, but closely related, meanings.

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Georges Gonthier

Georges Gonthier is a Canadian computer scientist and practitioner in formal mathematics.

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Gerhard Ringel

Gerhard Ringel (October 28, 1919 in Kollnbrunn, Austria – June 24, 2008 in Santa Cruz, California) was a German mathematician.

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Glossary of graph theory

This is a glossary of graph theory.

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Graph (discrete mathematics)

In discrete mathematics, particularly in graph theory, a graph is a structure consisting of a set of objects where some pairs of the objects are in some sense "related".

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Graph coloring

In graph theory, graph coloring is a special case of graph labeling; it is an assignment of labels traditionally called "colors" to elements of a graph subject to certain constraints.

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Graph theory

In mathematics, graph theory is the study of graphs, which are mathematical structures used to model pairwise relations between objects.

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Grötzsch's theorem

In the mathematical field of graph theory, Grötzsch's theorem is the statement that every triangle-free planar graph can be colored with only three colors. Four color theorem and Grötzsch's theorem are graph coloring, planar graphs and theorems in graph theory.

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Hadwiger conjecture (graph theory)

In graph theory, the Hadwiger conjecture states that if G is loopless and has no K_t minor then its chromatic number satisfies It is known to be true for The conjecture is a generalization of the four-color theorem and is considered to be one of the most important and challenging open problems in the field. Four color theorem and Hadwiger conjecture (graph theory) are graph coloring.

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Hadwiger–Nelson problem

In geometric graph theory, the Hadwiger–Nelson problem, named after Hugo Hadwiger and Edward Nelson, asks for the minimum number of colors required to color the plane such that no two points at distance 1 from each other have the same color. Four color theorem and Hadwiger–Nelson problem are graph coloring.

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Heawood conjecture

In graph theory, the Heawood conjecture or Ringel–Youngs theorem gives a lower bound for the number of colors that are necessary for graph coloring on a surface of a given genus. Four color theorem and Heawood conjecture are graph coloring and theorems in graph theory.

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Heinrich Heesch

Heinrich Heesch (June 25, 1906 – July 26, 1995) was a German mathematician.

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Heinrich Tietze

Heinrich Franz Friedrich Tietze (August 31, 1880 – February 17, 1964) was an Austrian mathematician, famous for the Tietze extension theorem on functions from topological spaces to the real numbers.

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Hugo Hadwiger

Hugo Hadwiger (23 December 1908 in Karlsruhe, Germany – 29 October 1981 in Bern, Switzerland) was a Swiss mathematician, known for his work in geometry, combinatorics, and cryptography.

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Immersion (mathematics)

In mathematics, an immersion is a differentiable function between differentiable manifolds whose differential pushforward is everywhere injective.

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John William Theodore Youngs

John William Theodore Youngs (usually cited as J. W. T. Youngs, known as Ted Youngs; 21 August 1910 Bilaspur, Chhattisgarh, India – 20 July 1970 Santa Cruz, California) was an American mathematician.

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Julius Petersen

Julius Peter Christian Petersen (16 June 1839, Sorø, West Zealand – 5 August 1910, Copenhagen) was a Danish mathematician.

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Kaliningrad Oblast

Kaliningrad Oblast (translit) is the westernmost federal subject of the Russian Federation, in Central and Eastern Europe.

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Kempe chain

In mathematics, a Kempe chain is a device used mainly in the study of the four colour theorem. Four color theorem and Kempe chain are graph coloring.

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Kenneth Appel

Kenneth Ira Appel (October 8, 1932 – April 19, 2013) was an American mathematician who in 1976, with colleague Wolfgang Haken at the University of Illinois at Urbana–Champaign, solved one of the most famous problems in mathematics, the four-color theorem.

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Kenneth O. May

Kenneth O. May (July8, 1915December 1977) was an American mathematician and historian of mathematics, who developed May's theorem.

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Klein bottle

In mathematics, the Klein bottle is an example of a non-orientable surface; that is, informally, a one-sided surface which, if traveled upon, could be followed back to the point of origin while flipping the traveler upside down.

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Kurt Gödel

Kurt Friedrich Gödel (April 28, 1906 – January 14, 1978) was a logician, mathematician, and philosopher.

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Lie algebra

In mathematics, a Lie algebra (pronounced) is a vector space \mathfrak g together with an operation called the Lie bracket, an alternating bilinear map \mathfrak g \times \mathfrak g \rightarrow \mathfrak g, that satisfies the Jacobi identity.

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Loop (graph theory)

In graph theory, a loop (also called a self-loop or a buckle) is an edge that connects a vertex to itself.

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MacTutor History of Mathematics Archive

The MacTutor History of Mathematics Archive is a website maintained by John J. O'Connor and Edmund F. Robertson and hosted by the University of St Andrews in Scotland.

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Map coloring

In cartographic design, map coloring is the act of choosing colors as a form of map symbol to be used on a map.

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Masterpiece

A masterpiece, magnum opus, or paren) in modern use is a creation that has been given much critical praise, especially one that is considered the greatest work of a person's career or a work of outstanding creativity, skill, profundity, or workmanship. Historically, a "masterpiece" was a work of a very high standard produced to obtain membership of a guild or academy in various areas of the visual arts and crafts.

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Mathematical proof

A mathematical proof is a deductive argument for a mathematical statement, showing that the stated assumptions logically guarantee the conclusion.

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Mathematics

Mathematics is a field of study that discovers and organizes abstract objects, methods, theories and theorems that are developed and proved for the needs of empirical sciences and mathematics itself.

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MathOverflow

MathOverflow is a mathematics question-and-answer (Q&A) website, which serves as an online community of mathematicians.

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Möbius strip

In mathematics, a Möbius strip, Möbius band, or Möbius loop is a surface that can be formed by attaching the ends of a strip of paper together with a half-twist.

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Microform

A microform is a scaled-down reproduction of a document, typically either photographic film or paper, made for the purposes of transmission, storage, reading, and printing.

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Missouri

Missouri is a landlocked state in the Midwestern region of the United States.

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Nakhchivan Autonomous Republic

The Nakhchivan Autonomous Republic (Naxçıvan Muxtar Respublikası) is a landlocked exclave of the Republic of Azerbaijan.

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Neil Robertson (mathematician)

George Neil Robertson (born November 30, 1938) is a mathematician working mainly in topological graph theory, currently a distinguished professor emeritus at the Ohio State University.

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Nevada

Nevada is a landlocked state in the Western region of the United States.

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Non-surveyable proof

In the philosophy of mathematics, a non-surveyable proof is a mathematical proof that is considered infeasible for a human mathematician to verify and so of controversial validity.

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Notices of the American Mathematical Society

Notices of the American Mathematical Society is the membership journal of the American Mathematical Society (AMS), published monthly except for the combined June/July issue.

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NP-completeness

In computational complexity theory, a problem is NP-complete when.

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Open set

In mathematics, an open set is a generalization of an open interval in the real line.

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Orientability

In mathematics, orientability is a property of some topological spaces such as real vector spaces, Euclidean spaces, surfaces, and more generally manifolds that allows a consistent definition of "clockwise" and "anticlockwise".

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Overseas France

Overseas France (France d'outre-mer, also France ultramarine) consists of 13 French territories outside Europe, mostly the remains of the French colonial empire that remained a part of the French state under various statuses after decolonization.

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Paul Seymour (mathematician)

Paul D. Seymour (born 26 July 1950) is a British mathematician known for his work in discrete mathematics, especially graph theory.

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Percy John Heawood

Percy John Heawood (8 September 1861 – 24 January 1955) was a British mathematician, who concentrated on graph colouring.

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Peter Guthrie Tait

Peter Guthrie Tait (28 April 18314 July 1901) was a Scottish mathematical physicist and early pioneer in thermodynamics.

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Philip Franklin

Philip Franklin (October 5, 1898 – January 27, 1965) was an American mathematician and professor whose work was primarily focused in analysis.

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Pie chart

A pie chart (or a circle chart) is a circular statistical graphic which is divided into slices to illustrate numerical proportion.

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Planar graph

In graph theory, a planar graph is a graph that can be embedded in the plane, i.e., it can be drawn on the plane in such a way that its edges intersect only at their endpoints. Four color theorem and planar graph are planar graphs.

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Proof assistant

In computer science and mathematical logic, a proof assistant or interactive theorem prover is a software tool to assist with the development of formal proofs by human–machine collaboration.

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Proof without words

In mathematics, a proof without words (or visual proof) is an illustration of an identity or mathematical statement which can be demonstrated as self-evident by a diagram without any accompanying explanatory text.

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Quartic function

In algebra, a quartic function is a function of the form where a is nonzero, which is defined by a polynomial of degree four, called a quartic polynomial.

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Robin Thomas (mathematician)

Robin Thomas (August 22, 1962 – March 26, 2020) was a mathematician working in graph theory at the Georgia Institute of Technology.

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RWTH Aachen University

RWTH Aachen University, in German Rheinisch-Westfälische Technische Hochschule Aachen, is a German public research university located in Aachen, North Rhine-Westphalia, Germany.

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Snark (graph theory)

In the mathematical field of graph theory, a snark is an undirected graph with exactly three edges per vertex whose edges cannot be colored with only three colors. Four color theorem and snark (graph theory) are graph coloring.

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Sphere

A sphere (from Greek) is a geometrical object that is a three-dimensional analogue to a two-dimensional circle.

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Szilassi polyhedron

In geometry, the Szilassi polyhedron is a nonconvex polyhedron, topologically a torus, with seven hexagonal faces.

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The Athenaeum (British magazine)

The Athenæum was a British literary magazine published in London, England, from 1828 to 1921.

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The Mathematical Intelligencer

The Mathematical Intelligencer is a mathematical journal published by Springer Science+Business Media that aims at a conversational and scholarly tone, rather than the technical and specialist tone more common among academic journals.

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The New York Times

The New York Times (NYT) is an American daily newspaper based in New York City.

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Theorem

In mathematics and formal logic, a theorem is a statement that has been proven, or can be proven.

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Tietze's graph

In the mathematical field of graph theory, Tietze's graph is an undirected cubic graph with 12 vertices and 18 edges.

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Time complexity

In theoretical computer science, the time complexity is the computational complexity that describes the amount of computer time it takes to run an algorithm.

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Toroidal polyhedron

In geometry, a toroidal polyhedron is a polyhedron which is also a toroid (a -holed torus), having a topological genus of 1 or greater.

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Torus

In geometry, a torus (tori or toruses) is a surface of revolution generated by revolving a circle in three-dimensional space one full revolution about an axis that is coplanar with the circle.

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Transitive relation

In mathematics, a binary relation on a set is transitive if, for all elements,, in, whenever relates to and to, then also relates to.

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Triangle-free graph

In the mathematical area of graph theory, a triangle-free graph is an undirected graph in which no three vertices form a triangle of edges.

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Triangulation (geometry)

In geometry, a triangulation is a subdivision of a planar object into triangles, and by extension the subdivision of a higher-dimension geometric object into simplices. Four color theorem and triangulation (geometry) are planar graphs.

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United States

The United States of America (USA or U.S.A.), commonly known as the United States (US or U.S.) or America, is a country primarily located in North America.

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University College London

University College London (branded as UCL) is a public research university in London, England.

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University of Illinois Urbana-Champaign

The University of Illinois Urbana-Champaign (UIUC, U of I, Illinois, or University of Illinois) is a public land-grant research university in the Champaign–Urbana metropolitan area, Illinois, United States.

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Vertex (graph theory)

In discrete mathematics, and more specifically in graph theory, a vertex (plural vertices) or node is the fundamental unit of which graphs are formed: an undirected graph consists of a set of vertices and a set of edges (unordered pairs of vertices), while a directed graph consists of a set of vertices and a set of arcs (ordered pairs of vertices).

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W. W. Rouse Ball

Walter William Rouse Ball (14 August 1850 – 4 April 1925), known as W. W.

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Wolfgang Haken

Wolfgang Haken (June 21, 1928 – October 2, 2022) was a German American mathematician who specialized in topology, in particular 3-manifolds.

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1-planar graph

In topological graph theory, a 1-planar graph is a graph that can be drawn in the Euclidean plane in such a way that each edge has at most one crossing point, where it crosses a single additional edge. Four color theorem and 1-planar graph are planar graphs.

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See also

Computer-assisted proofs

References

[1] https://en.wikipedia.org/wiki/Four_color_theorem

Also known as 4 color map problem, 4 color problem, 4 color theorem, 4 colour map problem, 4 colour theorem, 4-color conjecture, 4-color problem, 4-color theorem, 4-colors theorem, 4CT, Four Color Conjecture, Four Color Problem, Four Color Theory, Four Colour Theorem, Four color map problem, Four color map theorem, Four colour map problem, Four colour map theorem, Four colour problem, Four-Color Map Theorem, Four-Color Maps, Four-Color Theorem, Four-Colour Map Problem, Four-Colour Theorem, Four-color conjecture, Four-color map, Four-color map problem, Four-color problem, Four-colour map, Four-colour problem, History of the four color theorem, Map color problem, Map coloring problem, Map-coloring problem, Minimum number of map colors, Proof of the 4 color theorem, Seven colour theorem, The Four-Color map Theorem.

, Julius Petersen, Kaliningrad Oblast, Kempe chain, Kenneth Appel, Kenneth O. May, Klein bottle, Kurt Gödel, Lie algebra, Loop (graph theory), MacTutor History of Mathematics Archive, Map coloring, Masterpiece, Mathematical proof, Mathematics, MathOverflow, Möbius strip, Microform, Missouri, Nakhchivan Autonomous Republic, Neil Robertson (mathematician), Nevada, Non-surveyable proof, Notices of the American Mathematical Society, NP-completeness, Open set, Orientability, Overseas France, Paul Seymour (mathematician), Percy John Heawood, Peter Guthrie Tait, Philip Franklin, Pie chart, Planar graph, Proof assistant, Proof without words, Quartic function, Robin Thomas (mathematician), RWTH Aachen University, Snark (graph theory), Sphere, Szilassi polyhedron, The Athenaeum (British magazine), The Mathematical Intelligencer, The New York Times, Theorem, Tietze's graph, Time complexity, Toroidal polyhedron, Torus, Transitive relation, Triangle-free graph, Triangulation (geometry), United States, University College London, University of Illinois Urbana-Champaign, Vertex (graph theory), W. W. Rouse Ball, Wolfgang Haken, 1-planar graph.