View source for User:WordSeventeen/Notes

==Notations==
[[File:Copiale-cipher09s.png|950px|center|Copiale-cipher09s]]
Copiale Cipher; scaled page 16/17   2011  Source  [[Kevin Knight]], [http://stp.lingfil.uu.se/~bea/copiale/] Author 18th century

==maps==
[[File:1154 Tabula Rogeriana Al Idrisi transcripcion de Konrad Miller 1928 detalle.jpg|950px|center|1154 Tabula Rogeriana Al Idrisi transcripcion de Konrad Miller 1928 detalle]]
Detalle do noroeste da peninsula ibérica na Tábula Rogeriana de Al Idrisi, na transcripción latina de Konrad Miller de 1928. Pódese obter un mapa de detalle da Tábula Rogeriana na seguinte dirección á web da Libraría do Congreso dos EEUU.

==dyk ~ coding from David Eppstein==
===[[T:DYK|Did you know?]]===
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*... that [[James Colliander]], '''[[Gigliola Staffilani]]''', and [[Terence Tao]] are part of a collaborative group of mathematicians called the I-team? <small>([[Wikipedia:Recent additions/2015/January|15.01)]]</small>
*... that mathematician '''[[Linda Preiss Rothschild]]''' settled for graduate study at [[Massachusetts Institute of Technology|MIT]] after [[Princeton University|Princeton]] rejected her for being female? <small>([[Wikipedia:Recent additions/2015/January|15.01)]]</small>
*... that '''[[Ioana Dumitriu]]''' began taking graduate mathematics courses as a college freshman, and became the first female [[Putnam Fellow]] the following year? <small>([[Wikipedia:Recent additions/2015/January|15.01)]]</small>
*... that [[Pierre de Fermat|Fermat]]'s '''[[Fermat's right triangle theorem|only complete proof]]''' shows there is no [[Pythagorean triple|integer right triangle]] with square area, pair of integer right triangles sharing two sides, or square '''[[Congruum|gap between three equally spaced squares]]'''? <small>([[Wikipedia:Recent additions/2015/January|15.01)]]</small>
*[[File:K 4 crystal.JPG|right|100px]]... that the '''[[Laves graph]]''' ''(pictured)'', a highly symmetrical three-dimensional structure that forms one of the several [[allotropes of carbon|crystal structures of carbon]], is named after German crystallographer '''[[Fritz Laves]]'''? <small>([[Wikipedia:Recent additions/2014/December|14.12)]]</small>
*[[File:Haüy construction 129.svg|right|100px]]... that [[René Just Haüy]] modeled octahedral crystals mathematically as [[polycube]]s made of a '''[[centered octahedral number]]''' of cubes ''(pictured)''? <small>([[Wikipedia:Recent additions/2014/September|14.09)]]</small>
*... that [[Northwest Coast art]]ist '''[[Jim Hart (artist)|Jim Hart]]''' is a hereditary chief of the [[Council of the Haida Nation|Haida Nation]]? <small>([[Wikipedia:Recent additions/2014/August|14.08)]]</small>
*... that 19th-century French geometer '''[[Olry Terquem]]''', writing as "[[Sarfati|Tsarphati]]", was an outspoken advocate of the [[Reform movement in Judaism]]? <small>([[Wikipedia:Recent additions/2014/July|14.07)]]</small>
*... that mathematician and author '''[[C. Stanley Ogilvy]]''' was an avid sailor who frequently competed in the [[Star World Championships]]? <small>([[Wikipedia:Recent additions/2014/July|14.07)]]</small>
*... that '''[[book embedding]]s''' of [[Graph (mathematics)|graphs]] have been used to model [[fault-tolerant computer system]]s, the phases of [[traffic light]]s, and [[pseudoknot]]s in [[RNA]] molecules? <small>([[Wikipedia:Recent additions/2014/June|14.06)]]</small>
*[[File:1903 ball - Princess Olga K. Orlova (nee princess Beloselsky-Belozwersky).jpg|right|100px]]... that a photograph ''(pictured)'' taken by '''[[Elena Mrozovskaya]]''' at the [[1903 Ball in the Winter Palace]] in Saint Petersburg, Russia, was exhibited in the [[Hermitage Rooms]] in London 100 years later?<small>([[Wikipedia:Recent additions/2013/November|13.11]])</small>
*[[File:Quadrisecant.jpg|right|100px]]... that every [[Knot (mathematics)|knotted]] [[polygon]] in [[Euclidean space|three-dimensional space]] can be touched at four points by a '''[[Quadrisecant|quadrisecant line]]''' ''(pictured)''? <small>([[Wikipedia:Recent additions/2013/July|13.07]])</small>
*... that the subjects of '''[[Marjorie Senechal]]'''{{`s}} books include [[quasicrystal]]s, [[Albania]], and [[silk]]? <small>([[Wikipedia:Recent additions/2013/July|13.07]])</small>
*... that according to the '''[[Gilbert–Shannon–Reeds model]]''' of [[probability distribution]], a deck of [[playing card]]s should be riffled seven times in order to thoroughly randomize it? <small>([[Wikipedia:Recent additions/2013/July|13.07]])</small>
*[[File:Hyperbolic domains 642.png|right|100px]]... that [[M.&nbsp;C. Escher]]'s [[woodcut]] '''''[[Circle Limit III]]''''' was inspired by an illustration of a [[Uniform tilings in hyperbolic plane|hyperbolic tessellation]] ''(example pictured)'' in a paper by [[H.&nbsp;S.&nbsp;M. Coxeter]]? <small>([[Wikipedia:Recent additions/2013/July|13.07]])</small>
*... that mathematician '''[[Andrew Gleason]]''' liked to say that [[mathematical proof|proofs]] "really aren't there to convince you that something is true—they're there to show you why it is true"? <small>([[Wikipedia:Recent additions/2013/April|13.04]])</small>
*... that  Latvian-American mathematician '''[[Lipman Bers]]''' was also a [[human rights]] activist and a founder of the Committee on Human Rights of the [[National Academy of Sciences]]? <small>([[Wikipedia:Recent additions/2013/April|13.04]])</small>
*... that '''[[circular layout]]s''', in which the nodes of a graph are [[graph drawing|drawn]] on a circle, have been used to visualize the cyclic parts of [[metabolic network]]s? <small>([[Wikipedia:Recent additions/2013/March|13.03]])</small>
*... that '''[[William Allen Whitworth]]''' was the first mathematician to publish [[Bertrand's ballot theorem]], one of many [[List of misnamed theorems|misnamed mathematical theorems]]? <small>([[Wikipedia:Recent additions/2013/March|13.03]])</small>
*... that because of the possibility of [[List of dead heat horse races|dead heats]], the number of possible outcomes of a [[horse race]] is not a [[factorial]], but an '''[[ordered Bell number]]'''? <small>([[Wikipedia:Recent additions/2013/March|13.03]])</small>
*... that in the '''[[Graph power|square of a graph]]''', all vertices with a [[distance (graph theory)|distance]] of no more than two in the original graph are [[adjacency (graph theory)|adjacent]]? <small>([[Wikipedia:Recent additions/2013/March|13.03]])</small>
*... that '''[[Karl Beth]]''' is considered one of the founding fathers of the [[psychology of religion]]? <small>([[Wikipedia:Recent additions/2012/October|12.10]])</small>
*... that '''[[William W. Cooper]]''', a pioneer of [[management science]], dropped out of high school and worked as a professional [[boxing|boxer]] before becoming an academic? <small>([[Wikipedia:Recent additions/2012/October|12.10]])</small>
*... that '''[[Andrew Vázsonyi]]''' became past president of [[The Institute of Management Sciences]] without ever having been its president? <small>([[Wikipedia:Recent additions/2012/October|12.10]])</small>
*[[File:Pieter Nieuwland cropped.jpg|right|100px]]... that '''[[Pieter Nieuwland]]''' ''(pictured)'', an 18th-century child prodigy and [[polymath]] who died a year after becoming a professor, has been called the Dutch [[Isaac Newton]]? <small>([[Wikipedia:Recent additions/2012/September|12.09]])</small>
*... that a '''[[Tomahawk (geometry)|tomahawk]]''' may be used to [[Angle trisection|split an angle into three equal parts]], despite the impossibility of doing so with [[compass and straightedge]]? <small>([[Wikipedia:Recent additions/2012/September|12.09]])</small>
*... that '''[[John Hilliard (artist)|John Hilliard]]'''{{`}}s ''Cause of Death'' (1974) suggested four different interpretations of one [[Negative (photography)|photographic negative]]? <small>([[Wikipedia:Recent additions/2012/September|12.09]])</small>
*[[File:Prince Ruperts cube.png|right|100px]]... that '''[[Prince Rupert's cube]]''', named for [[Prince Rupert of the Rhine]], can pass through a square hole drilled into a smaller cube ''(pictured)''? <small>([[Wikipedia:Recent additions/2012/September|12.09]])</small>
*... that [[Nicolaas Govert de Bruijn|Nicolas de Bruijn]] was inspired to prove '''[[De Bruijn's theorem]]''' on packing [[brick]]s into boxes by his seven-year-old son's inability to pack some bricks into a box without wasted space? <small>([[Wikipedia:Recent additions/2012/September|12.09]])</small>
*... that the shape that encloses two given [[volume]]s and has the minimum possible [[surface area]] is the '''[[Double bubble conjecture|double bubble]]''' commonly formed by [[soap bubble]]s? <small>([[Wikipedia:Recent additions/2012/July|12.07]])</small>
*[[File:Alexander Blok - Noch, ulica, fonar, apteka.jpg|right|100px]]... that the success of the multi-language '''[[Wall poems in Leiden|wall poems]]''' ''(pictured)'' in [[Leiden]], [[South Holland]], inspired similar projects in [[Sofia]], [[Bulgaria]], and in Paris, France? <small>([[Wikipedia:Recent additions/2012/June|12.06]])</small>
*... that '''[[Albert Brahms]]''' kept the first known records of the [[tide]] levels on the North Sea coast of Germany? <small>([[Wikipedia:Recent additions/2012/May|12.05]])</small>
*... that artist '''[[Tina Mion]]''', of [[Winslow, Arizona]], grew up visiting the museums of her birthplace, [[Washington, D.C.]], whose [[National Portrait Gallery (United States)|National Portrait Gallery]] now holds two of her works in its permanent collection? <small>([[Wikipedia:Recent additions/2012/May|12.05]])</small>
*... that the number of ways to place ''n'' diagonally symmetric [[Rook (chess)|rooks]] on an ''n'' × ''n'' [[chessboard]] in such a way that no two rooks attack each other is a '''[[Telephone number (mathematics)|telephone number]]'''? <small>([[Wikipedia:Recent additions/2012/April|12.04]])</small>
*... that swarms of Japanese [[Mictyris|soldier crabs]] of the species '''''[[Mictyris guinotae]]''''', named after French biologist '''[[Danièle Guinot]]''', can be used in place of the [[billiard ball]]s in [[billiard-ball computer]]s? <small>([[Wikipedia:Recent additions/2012/April|12.04]])</small>
*... that the Latvian mathematician '''[[Emanuels Grīnbergs]]''' lost his job and his doctoral degree for serving in the [[Wehrmacht|German Army]] during World War&nbsp;II, but then regained both by writing a new thesis? <small>([[Wikipedia:Recent additions/2012/April|12.04]])</small>
*... that the '''[[Healdsburg Memorial Bridge]]''' in [[Healdsburg, California]], was the first steel bridge across the [[Russian River (California)|Russian River]]? <small>([[Wikipedia:Recent additions/2012/January|12.01]])</small>
*[[File:Kwan Tai exterior.jpg|right|100px]]... that the '''[[Temple of Kwan Tai]]''' in [[Mendocino, California]] ''(pictured)'' was founded by a survivor from a fleet of seven Chinese [[Junk (ship)|junks]], two of which landed on the California coast in 1854? <small>([[Wikipedia:Recent additions/2012/January|12.01]])</small>
*... that '''[[Hendy Woods State Park]]''', an [[Old-growth forest|old-growth]] [[Sequoia sempervirens|coast redwood]] forest in the [[Anderson Valley]] of northern California, is scheduled to be closed in 2012 because of state budget cuts? <small>([[Wikipedia:Recent additions/2012/January|12.01]])</small>
*[[File:Compound of three octahedra.svg|right|100px]]... that the central [[chameleon]] [[Cage (enclosure)|cage]] in [[M. C. Escher]]'s 1948 [[woodcut]] '''''[[Stars (M. C. Escher)|Stars]]''''' has the shape of a '''[[compound of three octahedra]]''' ''(pictured)''? <small>([[Wikipedia:Recent additions/2011/December|11.12]])</small>
*[[File:Jacob Ochtervelt - Street Musicians at the Doorway of a House - WGA16622.jpg|right|100px]]... that the '''[[Pythagorean tiling]]''', a pattern of [[Square (geometry)|squares]] of two sizes that can be used to prove the [[Pythagorean theorem]], appears in a painting ''(pictured)'' by [[Dutch Golden Age painting|Dutch Golden Age]] artist [[Jacob Ochtervelt]]? <small>([[Wikipedia:Recent additions/2011/October|11.10]])</small>
*... that despite leaving school at age 14, '''[[Thomas Kirkman]]''' became one of 19th-century England's leading mathematicians and helped found [[combinatorial design]] theory? <small>([[Wikipedia:Recent additions/2011/October|11.10]])</small>
*... that the '''[[Sint Servaasbrug]]''' in [[Maastricht]] has been called the oldest bridge in [[Netherlands|the Netherlands]], and was built in the 13th century to replace a [[Roman bridge]] that gave its name to the city? <small>([[Wikipedia:Recent additions/2011/October|11.10]])</small>
*... that '''[[Michel Demazure]]''', a mathematician from the [[pseudonym]]ous [[Nicolas Bourbaki]] group, led two French science museums, the [[Palais de la Découverte]] and the [[Cité des Sciences et de l'Industrie]]? <small>([[Wikipedia:Recent additions/2011/August|11.08]])</small>
*... that the '''[[De Bruijn–Erdős theorem (graph theory)|De Bruijn–Erdős theorem]]''' may be used to extend the [[four color theorem|four-color theorem]] from finite [[planar graph]]s to planar graphs with infinitely many vertices? <small>([[Wikipedia:Recent additions/2011/July|11.07]])</small>
*... that the '''[[Theil–Sen estimator]]''' can accurately [[linear regression|fit a line]] to a set of sample points even when up to 29% of the points have been [[Outlier|arbitrarily corrupted]]? <small>([[Wikipedia:Recent additions/2011/July|11.07]])</small>
*... that the '''[[Malfatti circles]]''', three [[tangent circles]] inside a triangle, are named after [[Gian Francesco Malfatti|Malfatti]] because of an incorrect conjecture he made, and were studied earlier by [[Ajima Naonobu|Ajima]] and di Cecco? <small>([[Wikipedia:Recent additions/2011/June|11.06]])</small>
*... that the '''[[widest path problem]]''' forms the [[algorithm]]ic basis of the [[Schulze method]] used by [[Wikimedia Foundation|Wikimedia]] to decide the winners of multiway [[election]]s? <small>([[Wikipedia:Recent additions/2011/May|11.05]])</small>
*[[File:Kawasaki's theorem.jpg|right|100px]]... that according to '''[[Kawasaki's theorem]]''', an [[origami]] [[crease pattern]] with one [[Vertex (geometry)|vertex]] may be [[Flat-foldability|folded flat]] ''(pictured)'' if and only if the sum of every other angle between consecutive creases is 180º? <small>([[Wikipedia:Recent additions/2011/April|11.04]])</small>
*... that '''[[John R. Isbell]]''' was the primary contributor to the mathematical theory of [[uniform space]]s? <small>([[Wikipedia:Recent additions/2011/April|11.04]])</small>
*... that '''[[Edgar Gilbert]]''' investigated the [[mathematics]] of [[shuffling]] [[playing card]]s? <small>([[Wikipedia:Recent additions/2011/March|11.03]])</small>
*... that, in the '''[[Rule 90]]''' [[cellular automaton]], any finite pattern eventually fills the whole array of cells with copies of itself? <small>([[Wikipedia:Recent additions/2011/February|11.02]])</small>
*... that '''''[[The Princeton Companion to Mathematics]]''''' is the 2011 winner of the [[Mathematical Association of America]]'s [[Euler Book Prize]]? <small>([[Wikipedia:Recent additions/2011/February|11.02]])</small>
*... that '''[[Block cellular automaton|block cellular automata]]''', invented by '''[[Norman Margolus]]''', can be used to simulate [[lattice gas automaton|lattice gas]]es, sand piles, and [[billiard-ball computer]]s? <small>([[Wikipedia:Recent additions/2011/February|11.02]])</small>
*[[File:Navarro River Redwoods.jpg|right|100px]]... that Charles Fletcher, the first European settler in what is now '''[[Navarro River Redwoods State Park]]''', built an inn in 1865 that remained open until the 1970s? <small>([[Wikipedia:Recent additions/2011/February|11.02]])</small>
*... that '''[[Andreu Mas-Colell]]''', currently the [[List of Ministers of Economy and Knowledge of Catalonia|Minister of Economy and Knowledge]] of [[Catalonia Government 2010-2014 term of office|Catalonia, Spain]], has studied [[general equilibrium theory]] by using [[differential topology]]? <small>([[Wikipedia:Recent additions/2011/January|11.01]])</small>
*... that '''[[Graciela Chichilnisky]]''', who proposed the [[Kyoto Protocol]]'s market for [[carbon credit]] [[emissions trading|trading]], obtained her PhDs in [[mathematics]] and [[economics]] without ever having been an [[undergraduate education#United States system|undergraduate]]? <small>([[Wikipedia:Recent additions/2011/January|11.01]])</small>
*... that [[Shapley–Folkman lemma#Shapley–Folkman theorem and Starr's corollary|Starr's corollary]] to the '''[[Shapley–Folkman lemma]]''' was proved by an undergraduate student of [[Kenneth J. Arrow|Kenneth Arrow]]? <small>([[Wikipedia:Recent additions/2010/October|10.10]])</small>
*... that [[Paul Erdős]] challenged '''[[Jon Folkman]]''' to solve [[mathematical problem]]s immediately after Folkman's surgery for brain cancer? <small>([[Wikipedia:Recent additions/2010/October|10.10]])</small>
*... that every [[round-robin tournament]] either has a set of players who win all games against players outside the set, or its [[tournament (graph theory)|graph of wins and losses]] is '''[[pancyclic graph|pancyclic]]''', having [[directed cycle]]s of all lengths? <small>([[Wikipedia:Recent additions/2010/September|10.09]])</small>
*[[File:Albion River Bridge.jpg|right|100px]]... that the '''[[Albion River Bridge]]''', the only [[wooden bridge]] on [[California State Route 1]], has been proposed for replacement by the [[California Department of Transportation]]? <small>([[Wikipedia:Recent additions/2010/August|10.08]])</small>
*... that [[Coretta Scott King]] called [[civil rights movement|African-American civil rights]] activist '''[[Randolph Blackwell]]''' an "unsung giant" of [[Nonviolence|nonviolent social change]]? <small>([[Wikipedia:Recent additions/2010/August|10.08]])</small>
*[[File:Ten Mile River (California).jpg|right|100px]]... that the number of [[coho salmon]] [[Spawn (biology)|spawning]] on the '''[[Ten Mile River (California)|Ten Mile River]]''' in [[Mendocino County, California]], has dropped precipitously since the 1960s? <small>([[Wikipedia:Recent additions/2010/August|10.08]])</small>
*... that '''[[Konocti Harbor]]''', a now-closed [[resort]] and [[music venue]] in [[Lake County, California]], was originally founded in 1959 as low-cost vacation housing for members of a [[plumber]]s [[trade union|union]]? <small>([[Wikipedia:Recent additions/2010/August|10.08]])</small>
*... that [[Mendocino, California]], artist '''[[Bill Zacha]]''' learned to paint [[Left-handedness|left-handed]] after injuring his right hand in a fall? <small>([[Wikipedia:Recent additions/2010/June|10.06]])</small>
*... that Canadian [[astrophysics|astrophysicist]] '''[[Victoria Kaspi]]''' was one of the first to observe the [[millisecond pulsar|cosmic recycling]] of [[pulsar]]s? <small>([[Wikipedia:Recent additions/2010/February|10.02]])</small>
*[[File:Pizza theorem1.jpg|right|100px]]... that, according to the '''[[pizza theorem]]''', a [[disk (mathematics)|circular]] [[pizza]] that is sliced off-center into eight equal-angled wedges can still be [[fair division|divided equally]] between two people? <small>([[Wikipedia:Recent additions/2009/December|09.12]])</small>
*... that the '''[[clique problem]]''' of programming a computer to find [[complete graph|complete]] [[Glossary of graph theory#Subgraphs|subgraphs]] in an [[undirected graph]] was first studied as a way to find groups of people who all know each other in [[social network]]s? <small>([[Wikipedia:Recent additions/2009/December|09.12]])</small>
*... that [[psychiatrist]] '''[[Marie Nyswander]]''', who developed the [[methadone]] treatment for [[heroin]] [[drug addiction|addicts]], was herself addicted to [[cigarettes]]? <small>([[Wikipedia:Recent additions/2009/December|09.12]])</small>
*... that '''[[Matthew T. Dickerson]]''' is a [[computational geometry|computational geometer]], scholar of [[J. R. R. Tolkien]] and the [[Inklings]], novelist, [[blues]] [[musician]], [[fly fisherman]], [[maple sugar]] [[farmer]], and [[beekeeper]]? <small>([[Wikipedia:Recent additions/2009/November|09.11]])</small>
*[[File:Herschel graph.svg|right|100px]]... that the '''[[Herschel graph]]''' ''(pictured)'' is the smallest possible [[polyhedral graph]] that does not have a [[Hamiltonian cycle]]? <small>([[Wikipedia:Recent additions/2009/October|09.10]])</small>
*[[File:Phloxhirsuta.jpg|right|100px]]... that '''[[Yreka phlox]]''', an [[endangered species|endangered]] flowering plant that grows in [[serpentine soil]], is the official city flower of [[Yreka, California]]? <small>([[Wikipedia:Recent additions/2009/September|09.09]])</small>
*... that a casket discovered by '''[[Anant Sadashiv Altekar]]''' near [[Vaishali (ancient city)|Vaishali]], on display at the [[Patna Museum]], is said to contain the remains of the [[Buddha]]? <small>([[Wikipedia:Recent additions/2009/September|09.09]])</small>
*... that '''[[Martin Demaine]]''' founded the first one-man [[art glass]] [[art studio|studio]] in Canada and [[homeschooling|home-schooled]] his son [[Erik Demaine|Erik]] to become [[Massachusetts Institute of Technology|MIT]]{{'}}s youngest ever professor despite not having a college degree himself? <small>([[Wikipedia:Recent additions/2009/September|09.09]])</small>
*[[File:Russian Gulch Beach.jpg|100x100px|right|Frederick W. Panhorst Bridge]]... that the '''[[Frederick W. Panhorst Bridge]]''' ''(pictured)'', a [[concrete]] [[spandrel|open-spandrel]] [[arch bridge]] in '''[[Russian Gulch State Park]]''' near [[Mendocino, California]], replaced an earlier wooden [[trestle bridge]] in 1940? <small>([[Wikipedia:Recent additions/2009/August|09.08]])</small>
*... that the '''[[Life without Death]]''' [[cellular automaton]], a mathematical model of [[pattern formation]], is a variant of [[Conway's Game of Life]] in which cells, once brought to life, never die? <small>([[Wikipedia:Recent additions/2009/June|09.06]])</small>
*... that '''[[Donald G. Fink]]''', later to become a prominent [[electrical engineer]], was selected as the best [[orator]] in his county at a high school competition? <small>([[Wikipedia:Recent additions/2009/June|09.06]])</small>
*[[File:Calkin-Wilf_spiral.svg|right|100px]]... that one can list every [[positive number|positive]] [[rational number]] without repetition by [[breadth-first search|breadth-first traversal]] of the '''[[Calkin–Wilf tree]]'''? <small>([[Wikipedia:Recent additions/2009/May|09.05]])</small>
*... that the first textbook in [[Hungarian language|Hungarian]], an [[encyclopedia]] by '''[[János Apáczai Csere]]''', was written and published in [[The Netherlands]]? <small>([[Wikipedia:Recent additions/2009/March|09.03]])</small>
*[[File:Hadwiger covering.svg|right|100px]]... that the '''[[Hadwiger conjecture (combinatorial geometry)|Hadwiger conjecture]]''' ''(diagram pictured)'' implies that the surface of any [[Solid geometry|three-dimensional]] [[convex body]] can be [[Lighting|illuminated]] by only eight light sources, but the best [[Mathematical proof|proven]] bound is that 16 lights are sufficient? <small>([[Wikipedia:Recent additions/2009/March|09.03]])</small>
*[[File:Equitable-K15.svg|right|100px]]... that an '''[[equitable coloring]]''' of a [[undirected graph|graph]] ''(pictured)'', in which the numbers of vertices of each color are as nearly equal as possible, may require far more colors than a [[graph coloring]] without this constraint? <small>([[Wikipedia:Recent additions/2009/March|09.03]])</small>
*... that no matter how [[fair coin|biased a coin]] one uses, [[coin flipping|flipping a coin]] to determine whether each [[edge (graph theory)|edge]] is present or absent in a [[countability|countably infinite]] [[undirected graph|graph]] will always produce [[graph isomorphism|the same graph]], the '''[[Rado graph]]'''? <small>([[Wikipedia:Recent additions/2009/March|09.03]])</small>
*... that '''[[Victor Vacquier]]''' escaped [[Russian Civil War|Russia]] by sleigh across the frozen [[Gulf of Finland]] and went on to pioneer the use of [[Magnetic anomaly detector|submarine detectors]] for investigating [[plate tectonics]]? <small>([[Wikipedia:Recent additions/2009/February|09.02]])</small>
*... that there are 115,200 solutions to the '''[[ménage problem]]''' of [[permutation|permuting]] six couples at a twelve-person table so that men and women alternate and are seated away from their partners? <small>([[Wikipedia:Recent additions/2009/January|09.01]])</small>
*[[File:Hadwiger conjecture.svg|right|100px]]... that [[mathematician]] [[Paul Erdős]] called the '''[[Hadwiger conjecture (graph theory)|Hadwiger conjecture]]''', a still-open generalization of the [[four-color problem]], "one of the deepest unsolved problems in [[graph theory]]"? <small>([[Wikipedia:Recent additions/2008/May|08.05]])</small>
*...that [[Netherlands|Dutch]] [[topology|topologist]] '''[[Johannes De Groot]]''' is the [[academic genealogy|academic grandfather]], great-grandfather, and great-great-grandfather of his [[namesake]] via four different paths of academic supervision? <small>([[Wikipedia:Recent additions/2008/April|08.04]])</small>
*...that '''[[Carl Størmer]]''', "the acknowledged authority" on [[Aurora (astronomy)|aurorae]] and the motion of charged particles in the [[magnetosphere]], began his academic career inventing [[Machin-like formula|formulae]] for [[Pi|π]]? <small>([[Wikipedia:Recent additions/2008/March|08.03]])</small>
*...that [[Scripps Institution of Oceanography|Scripps]] [[Chemical oceanography|marine chemist]] '''[[Edward D. Goldberg]]''' suggested using [[mussel]]s to measure the amount of [[marine pollution|pollution in the oceans]]? <small>([[Wikipedia:Recent additions/2008/March|08.03]])</small>
*...that [[television]] pioneer '''[[Thomas T. Goldsmith Jr.|Thomas T. Goldsmith, Jr.]]''' became the inventor of the [[video game]] when he took out a video game [[patent]] in 1948? <small>([[Wikipedia:Recent additions/2008/March|08.03]])</small>
*...that in [[Cycle detection#Algorithms|Floyd's algorithm]] for '''[[cycle detection]]''', the [[The Tortoise and the Hare|tortoise and hare]] move at very different speeds, but always finish at the same spot? <small>([[Wikipedia:Recent additions/2007/October|07.10]])</small>
*...that in [[graph theory]], a '''[[pseudoforest]]''' can contain [[tree (graph theory)|trees]] and pseudotrees, but cannot contain any butterflies, diamonds, handcuffs, or bicycles? <small>([[Wikipedia:Recent additions/2007/October|07.10]])</small>
*[[Image:Möbius–Kantor unit distance.svg|right|100px]]...that it is not possible to [[Projective configuration|configure]] two mutually [[inscribe]]d [[quadrilateral]]s in the [[Euclidean plane]], but the '''[[Möbius–Kantor graph]]'''  ''(pictured)'' describes a solution in the [[complex projective plane]]? <small>([[Wikipedia:Recent additions/2007/September|07.09]])</small>
*...that the six [[permutation]]s of the [[vector space|vector]] (1,2,3) form a [[hexagon]] in [[Euclidean space|3d space]], the 24 permutations of (1,2,3,4) form a [[truncated octahedron]] in [[Four-dimensional space|four dimensions]], and both are examples of '''[[Permutohedron|permutohedra]]'''? <small>([[Wikipedia:Recent additions/2007/August|07.08]])</small>
*[[Image:JohnHooperBalancing.jpg|right|100px]]...that [[Canada|Canadian]] sculptor '''[[John Hooper (sculptor)|John Hooper]]'''  ''(sculpture pictured)'' previously lived in [[England]], [[China]], [[India]], and [[South Africa]], and was a captain in the [[British Army]]? <small>([[Wikipedia:Recent additions/2007/August|07.08]])</small>
*...that the '''[[Rule 184]]''' [[cellular automaton]] can simultaneously model the [[traffic flow|behavior of cars moving in traffic]], the [[Deposition (Aerosol physics)|accumulation of particles on a surface]], and particle-antiparticle [[annihilation]] reactions? <small>([[Wikipedia:Recent additions/2007/May|07.05]])</small>
[[Image:2dCCA-n16.png|right|100px]]
*...that a '''[[cyclic cellular automaton]]''' ''(pictured)'' is a system of simple mathematical rules that can generate complex patterns mixing random chaos, blocks of color, and spirals? <small>([[Wikipedia:Recent additions/2007/April|07.04]])</small>
*...that a nonconvex [[polygon]] with three [[convex set|convex]] vertices is called a '''[[pseudotriangle]]'''? <small>([[Wikipedia:Recent additions/2007/April|07.04]])</small>
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