Nov 18, 2010
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Oct 22, 2010
MATHEMATICS OF THE DISCRETE FOURIER TRANSFORM (DFT) WITH AUDIO APPLICATIONS SECOND EDITION
Oct 18, 2010
Oct 12, 2010
MIT OCW 18.03 Differential Equations Video Lectures Spring 2004 : Free Download
Lecture 01 (mpeg4)
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Other Files
Oct 8, 2010
Universe Queen » Blog Archive » Project Euler（50）
Aug 7, 2010
Network inftrastructure analysis
New articles (last 12) 
23 Jun  arXiv:1006.4257 Impact of network structure on competitive evolutionary processes. V. Nicosia, F. Bagnoli, V. Latora. physics.socph (nlin.PS physics.statmech). 
22 Jun  arXiv:1006.3923 Complex Networks and Symmetry: a Review with Applications to the Evolution of World Trade. Franco Ruzzenenti, Diego Garlaschelli, Riccardo Basosi. physics.socph (nlin.AO physics.statmech). 
22 Jun  arXiv:1006.3863 Normalization of research evaluation results across academic disciplines. Ralph Kenna, Bertrand Berche. physics.socph (cs.DL). 
Crosslistings 
23 Jun  arXiv:1006.4294 NetzCope: A Tool for Displaying and Analyzing Complex Networks. Michael J. Barber, Ludwig Streit, Oleg Strogan. physics.dataan (physics.socph). 
23 Jun  arXiv:0902.0878 Backbone of complex networks of corporations: The flow of control. J. B. Glattfelder, S. Battiston. Phys. Rev. E 80, 036104 (2009). qfin.GN (physics.socph). 
21 Jun  arXiv:1006.3708 Econophysics studies in Estonia. M. Patriarca, E. Heinsalu, R. Kitt, J. Kalda. qfin.GN (physics.socph). 
Revisions 
22 Jun  arXiv:1003.0088 A Condition for Cooperation in a Game on Complex Networks. Tomohiko Konno. physics.socph. 
22 Jun  arXiv:1002.3282 Cooperation in the snowdrift game on directed smallworld networks under selfquestioning and noisy conditions. Tian Qiu, Tarik Hadzibeganovic, Guang Chen, LiXin Zhong, XiaoRun Wu. physics.socph (cs.GT physics.compph qbio.PE). 
Revised crosses 
23 Jun  arXiv:0911.4729 Hearing the clusters in a graph: A distributed algorithm. Tuhin Sahai, Alberto Speranzon, Andrzej Banaszuk. math.CO (cs.DC physics.compph physics.socph). 
23 Jun  arXiv:0809.1040 Patterns in highfrequency FX data: Discovery of 12 empirical scaling laws. J. B. Glattfelder, A. Dupuis, R. B. Olsen. qfin.ST (physics.socph). 
22 Jun  arXiv:0909.3257 The Shield that Never Was: Societies with SinglePeaked Preferences are More Open to Manipulation and Control. P. Faliszewski, E. Hemaspaandra, L. A. Hemaspaandra, J. Rothe. URCS TR2009950. cs.GT (cs.CC cs.MA physics.socph). 
22 Jun  arXiv:0908.1879 Multinetwork of international trade: A commodityspecific analysis. Matteo Barigozzi, Giorgio Fagiolo, Diego Garlaschelli. Physical Review E 81, 046104 (2010). qfin.GN (physics.socph physics.statmech). 
Jul 27, 2010
New Zealand Maths Olympiad Committee online
Limits, continuity and completeness
Wednesday, April 8, 2009 22:09Occasionally, in contest problems, it helps to have a careful understanding of real numbers and realvalued functions. But what, exactly, is a real number? These Auckland squad training lecture notes by Heather Macbeth outline some basics.
(Update, 19/4/09: several errors fixed.)
Polynomials, pure mathematics, Princeton Companion
Thursday, April 2, 2009 13:23Round about sixth form one learns that every polynomial can be factorized, as a product of linear factors. Why? Well, here’s a polynomial, see. It’s probably a cubic with integer coefficients — after all, most nontrivial polynomials that one encounters are. You play with it until you discover a root, likely by looking at integer factors of the highest and lowest coefficients. Then you polynomialdivide through by the linear factor which that root gives you, and get a quadratic, whose roots there’s a formula for finding. Tada!
Of course, there’s a problem with this algorithm: it depends on figuring out how to break down your polynomial into only linear and quadratic factors.
Recurrence relations
Tuesday, January 27, 2009 17:06Some notes and problems on finding and solving recurrence relations. Read these if you’ve ever wondered how to find a formula for the Fibonacci sequence!
Symmetric polynomials
Monday, January 26, 2009 15:56These notes by Arkadii Slinko explain how to extract information from symmetric polynomials of a set of variables, and how to break any symmetric polynomial down into a few simple ones. The final section gives some applications to triangle geometry.
Functional equations
Sunday, January 25, 2009 1:36These notes by Arkadii Slinko cover techniques — some standard, some exotic — for solving functional equations: groups of substitutions, commutativity, the Cauchy functional equation.
Solutions to some of the problems are available, and can be obtained by writing to nzmathsolymp@gmail.com.
Convex functions
Wednesday, January 14, 2009 21:08Notes from Heather Macbeth’s algebra lecture at the January 2009 camp.
(Update, 24/1/2009: some typos fixed.)
Jul 26, 2010
More Math Videos!
More Math Videos!
Below are several mathrelated videos produced by others. We'll add more periodically. Please let us know of others we should add to our collection.
Beautiful Math 
International Mathematics Olympiad
PDATED (March 2007) Recommended literature, such as Paul Zeitz' The Art and Craft of Problem Solving 

Amazon Kindle 2, Amazon's new ereader for digital books 
More about IMO: HARD PROBLEMS: The Road to the World's Toughest Math Contest 
The International Mathematics Olympiad (IMO, also known as the International Mathematical Olympiad) is an annual mathematics competition for high school students [IMO Article in Wikipedia]. It is one  in fact, the oldest  of the International Science Olympiads. The first IMO was held in Romania in 1959. The problems come from various areas of mathematics, such as are included in math curricula at secondary schools. Finding the solutions of these problems, however, requires exceptional mathematical ability and excellent mathematical knowledge on the part of the contestants.
Topics covered (see Unwritten Syllabus and Tutorials at Arkadii Slinko's Math Olympiad Website, currently being transferred):
 Number Theory, including
 Fundamental Theorems on Arithmetic
 Linear and quadratic Diophantine equations, including Pell's equation
 Arithmetic of residues modulo n, Fermat's and Euler's theorems
 Algebra, including
 Fundamental Theorems on Algebra, e.g. inequalities, factorization of a polynomial into a product of irreducible polynomials
 Symmetric polynomials of several variables, Vieta's theorem
 Combinatorics, including
 Graph theory
 Geometry, including
 Properties of the orthocentre, Euler's line, ninepointcircle, Simson line, Ptolemy's inequality, Ceva and Menelaus etc.
 Calculus (!)
 Complex numbers (though present in the past)
 Inversion in geometry
 Solid geometry (though present in the past; may return)
The usual size of an official delegation to an IMO is (a maximum of) six student competitors and (a maximum of) two leaders. There is no official ``team''. The student competitors write two papers, on consecutive days, each paper consisting of three questions. Each question is worth seven marks. (The preceding information is taken from an Overview of the IMO provided by the IMO'95 host country, Canada; also see below.) A total score of 42 points is possible. Awards are determined as follows:
 GOLD MEDAL: the top 1/12 of scores receive gold medals
 SILVER MEDAL: the next 2/12 of scores receive silver medals
 BRONZE MEDAL: the next 3/12 of scores receive bronze medals
 HONORABLE MENTION: any competitor who receives a perfect score of 7 on any one question, but who does not receive a medal, is awarded an honorable mention
My report on IMO 2002 provides further details of how the IMO is run.
A list of recommended mathematics literature for selfstudy is slowly evolving.
Contents
 General Information
 International Mathematics Competitions
 Regional Mathematics Competitions
 National Mathematics Competitions
 Archives and Link Collections
 Schools
 Mathematics on WWW
 Miscellaneous Links
Without doubt, these lists of web addreses are far from complete. If you send relevant web addresses that are not listed here, then they will be included.
General Information
 Official IMO web site < < < < < N E W
 A new website about the IMO, including a problem and results archive.
 Logos
 An overview of all available logos

Regulations  Regulations Pertaining to the IMO
 These Regulations define the IMO as of ?. New aspects are the IMO Advisory Board and the IMO Trust Fund.
 General (but not official) IMO site

Future IMOs  IMO 2009
 The 50th IMO will be hosted by Germany in Bremen on 1022 July, 2009.
 IMO 2010
 The 51st IMO will be hosted by Kazakhstan in ? on ?? ?, 2010.
 IMO 2011
 The 52nd IMO will be hosted by the Netherlands in ? on ?? ?, 2011.

Past IMOs  IMO 2008 [ local files ]
 The 49th IMO was hosted by Spain in Madrid on 1022 July, 2008. (arrival day for contestants is 14 July).
 IMO 2007 [ local files: logo  problems day 1, day 2 ]
 The 48th IMO was hosted by Vietnam in Hanoi on 1931 July, 2007 (arrival day for contestants is 23 July).
 IMO 2006 [ local files: about  logo  problems day 1, day 2  solutions  results ]
 The 47th IMO was hosted by Slovenia in Ljubljana on 618 July, 2006.
 IMO 2005 [ local files:  about  logo  rules  countries  problems day 1, day 2  results ]
 The 46th IMO was hosted by Mexico in Mérida, Yucatán, on 819 July, 2005.
 IMO 2004 [ logo  rules  problems day 1, day 2  all data  UK report incl. problems ]
 The 45th IMO was hosted by Greece in Athens on 618 July, 2004.
 IMO 2003 [ old address  English  logo  results (Excel)  problems day 1, day 2  solutions ]
 The 44th IMO was hosted by Japan in Tokyo on 719 July, 2003. Submission deadline for problems was 15 Feb. 2003.
 IMO 2002 [ logo  problems in PDF (Dutch)  results  statistics  personal report  shortlist is confidential until IMO2003 ]
 The 43rd IMO was hosted by the United Kingdom in Glasgow on 1930 July, 2002.
 IMO 2001, Scoring Site [ logo  problems in PDF  problems and solution as Mathematica Notebook  results  mailing list  shortlist  book ]
 The 42nd IMO was hosted by the United States of America in Washington DC on 114 July, 2001.
 IMO 2000 [ logo  regulations  problems day 1  problems day 2  problems in PDF  results  medals  mailing list ]
 The 41st IMO was hosted by South Korea in Taejon on 1325 July, 2000.
 IMO 1999 [ logo  problems day 1  problems day 2  results  mailing list ]
 The 40th IMO was hosted by Romania in Bucharest on 1022 July, 1999.
 IMO 1998 [ logo  problems  results ]
 The 39th IMO was hosted by Taiwan in Taipei on 1021 July, 1998.
 IMO 1997 [ logo  problems day 1  problems day 2  results ]
 The 38th IMO was hosted by Argentina in Mar del Plata on July 1831, 1997. There is an IMO97 mailing list.
 IMO 1996 [ logo  the problems ]
 The 37th IMO was hosted by India in Mumbai (Bombay) on July 517, 1996.
Contact information:
Professor A.M. Vaidya
IMOCell, School of Mathematics,
Tata Institute of Fundamental Research
Homi Bhabha Road, Mumbai (Bombay) 400005
IndiaTelephone:91(022) 2152971, 2152311, 2188654
Telefax: 91 (022) 2152110/2152181
Email: imo@tifrvax.tifr.res.in or imo@math.tifr.res.in
 IMO 1995 [ logo  regulations  the problems ]
 The 36th IMO was hosted by Canada in Toronto on July 1028, 1995.
 IMO 1994 [ logo  the problems and results ]
 The 35th IMO was hosted by Hong Kong on July 1219, 1994.
 IMO 1993 [ logo  problems day 1  problems day 2 ]
 The 34th IMO was hosted by Turkey in Istanbul on July 1219, 1993.

Journals and other info  IMOnet
 The network for the participants to the IMO. Has information on three mailing lists (for IMO'99, IMO2000, and IMO problems).
 IMO News at MAA
 The Mathematical Association of America (MAA) carries some information on the IMO and publishes books with IMO problems.
 IMO Scores
 This site has some statistics about scores at IMO 1993 an on (except 1994). Maintained by Joseph Myers.
 KöMaL  Mathematical and Physical Journal for Secondary Schools
 More than one hundred years ago, Dániel Arany, a high school teacher from the city of Gyõr, decided to found a mathematical journal for high school students. His goal was "to give a wealth of examples to students and teachers". The journal's first edition appeared on January 1, 1894.
 MathPro Press
 MathPro Press specializes in the publication of compendiums and indexes of mathematics problems.
 WFNMC
 The World Federation of National Mathematics Competitions (WFNMC) publishes a journal entitled Mathematics Competitions. Also see Australia below.
 M&IQ
 The Mathematics and Informatics Quarterly is an international journal which:
 Publishes articles, notes, problems and solutions in school mathematics and informatics.
 Is devoted to teachers and students, who are interested in mathematics and informatics clubs, olympiads and competitions.
 In the World of Mathematics
 This new quarterly journal is aimed at pupils, students, and teachers interested in mathematical problems and puzzles as well as in the history of mathematics and its new trends.
 SIPROMA Bulletin (in Spanish)
 SIPROMA is the ``Sociedad Iberoamericana para la Promoción de la Matemática''.
International Mathematics Competitions
 Kangourou Sans Frontières / Kangaroo without Frontiers: International Mathematics Competition (French site)
 Kangourou Sans Frontières (KSF) is an international mathematics competition for various levels of students. History and Rules (old)
 France: Le Kangourou de Mathématiques
 Germany: Känguru der Mathematik
 Italy: Kangourou Italia
 Netherlands: Wiskunde Kangoeroe
 Poland: Kangur Matematyczyny
 Russia: Kenguru
 United States of America: Math Kangaroo
 Mathematical Olympiads for Elementary and Middle Schools
 Created in 1977 by Dr. George Lenchner, an internationally known math educator, the Math Olympiads went public in 1979. In the year 2000, over 120,000 students from 5,000 teams worldwide participated in the Olympiads, representing 26 countries.
 International Living Maths Mathletics Olympiad <<<<< N E W
 Living Maths (South Africa) organizes the International Living Maths Mathletics Olympiad for ages 6 to 13 (K7). Look under: Events, Olympiad.
 Mental Calculation World Cup
Regional Mathematics Competitions
 Asian Pacific Mathematics Olympiad
 Problems in English and French.
 Balkan Math Olympiad
 No link yet.
 Bay Area Mathematical Olympiad
 The Bay Area Mathematical Olympiad (BAMO) is a contest for high school students sponsored jointly by the Mathematical Sciences Research Institute (MSRI), the American Institute of Mathematics (AIM), the University of California at Berkeley (UCB), and the University of San Francisco (USF).
 Colorado Mathematical Olympiad
 The Colorado Mathematical Olympiad (CMO) is the largest essaytype mathematical competition in the United States, with 600 to 1,000 participants competing annually for fine prizes.
 IberoAmerican Mathematics Olympiad
 Home page (in Spanish) of the Olimpíadas Iberoamericanas de Matemática (OIM).
 The Math League (USA & Canada)
 The Math League is dedicated to bringing challenging mathematics materials to students, and specializes in math contests (for high schools in the USA and Canada), books, and computer software.
National Mathematics Competitions
 Argentina
 The Olimpíada Matemática Argentina (OMA) is the Argentinian Mathematics Olympiad. Currently, information is only available in Spanish.
 Australia
 The Australian Mathematics Trust (AMT) is a national nonprofit organization which conducts mathematics competitions in Australia. Includes information on theWFNMC.
 Belgium
 Information about the Mathematics Olympiads in Belgium:
 The Flanders Mathematics Olympiad (Vlaamse Wiskunde Olympiade = VWO), maintained by Paul G. Igodt (Paul.Igodt@kulak.ac.be).
 The Olympiade Mathématique Belge (OMB).
 Brazil [ also see here ]
 Information about the Brazilian Mathematics Olympiad (OBM=Olimpíada Brasileira de Matemática). All material in Portuguese only.
 Bulgaria
 Information about the National Mathematical Olympiad in Bulgaria as part of the Bulgarian Competitions in Mathematics and Informatics.
 Canada
 Information about the Canadian Mathematics Competition (CMC) maintained by Ruth Malinowski (cmc@math.uwaterloo.ca).
The Canadian Mathematical Society also has an Olympiads Home Page.
 Colombia
 The WWW Home Page for the Colombian Olympiads (in Spanish), covering Mathematics, Phyisics, and Informatics, maintained by Fernando Vega Salamanca (fvega@zulima.uanarino.edu.co).
Email: olimpia@federman.uanarino.edu.co  Czech Republic
 Denmark
 Estonia
 Information about the Estonian Matemaatika Olümpiaadid (also in the Estonian language), maintained by Uve Nummert (uve@math.ut.ee). Includes IMO information (in English).
 France
 Information about mathematics competitions in France, includes French translations of IMO problem sets and recommended French mathematics literature for IMO preparation.
 Germany
 The Verein MathematikOlympiaden e.V. coordinates the German Mathematics Olympiads (DeMO). There is also information available about the German Mathematics Olympiad 1995.
 Ireland
 Information on Irish participation in the International Mathematical Olympiads and (eventually) copies of Irish Maths Olympiad questions and photographs. Contact: Gordon Lessells (gordon.lessells@ul.ie).
 Israel
 Italy
 Information on the Italian (?) Mathematics Olympiad (in Italian). Email contact: mvillani@cibs.sns.it
 Japan
 Information about the IMO in general (starting from 34th) and the Mathematical Olympiad Foundation of Japan. Maintained by Naomasa Maruyama (maruyama@ism.ac.jp).
 Luxembourg
 Mexico
 Information (in Spanish) on the Mexican Mathematics Olympiad (OMM) and problem sets (mostly in Spanish) of various (regional) mathematics contests. Email:omm@hp.fciencias.unam.mx. Maintained by Felipe Lemaitre Carabias (iker@hardy.fciencias.unam.mx).
There is also an unofficial page for the Mexican Mathematical Olympiad (in Spanish), maintained by Pedro Sánchez.
Pierre Fermat Math Competition (in Spanish: Concurso de Matemáticas Pierre Fermat).
 The Netherlands
 Information about the Dutch Mathematics Olympiad (now also in English), maintained by Tom Verhoeff (Tom.Verhoeff@acm.org).
 New Zealand
 Information about the New Zealand Math Olympiads
 Norway
 The Niels Henrik Abels Mathematics Competition selects students for partiticipation in the IMO. This site also contains problem sets of the Norwegian Mathematical Olympiad and the IMO, including some solutions and results. Maintained by Einar Andreas Rødland (einara@math.uio.no).
 Panama
 Peru
 Information about Peru's math olympiad and the Cono Sur olympiads, maintained by Enrique Valeriano (evaleri@pucp.edu.pe).
 Poland
 Information (including problem sets) on the math olympiads in which Polish high school students participate (in particular: the Polish Mathematical Olympiad, the AustrianPolish Mathematics Competition, and the Baltic Team Contest). Maintained by Krzysztof Chelminski (chel@mathematik.thdarmstadt.de) and Waldemar Pompe (waldipo@mimuw.edu.pl).
 Portugal
 Olimpíadas Portuguesas de Matemática.
 Singapore
 Information about the IMO and Singapore's participation.
 Slovakia
 Mathematical olympiad in Slovakia.
 Slovenia
 Mathematical competitions in Slovenia are supervised by DMFA.
 South Africa
 South African Mathematics Olympiad.
 Spain
 Information and problem sets (in Spanish) for the math olympiads in which Spanish high school students participate, including the Spanish Mathematics Olympiad (Olimpiada Matemática Española = OME). Maintained by Cristobal Sánchez Rubio (csanchez@platea.pntic.mec.es).
Unoficcial Spanish Math Olympiad page maintained by Ramon Esteban Romero (Ramon.Esteban@uv.es).
 Switzerland
 Information about the Swiss participation in the IMO in English, French, German, Italian.
 United Kingdom
 Information about the British Mathematical Olympiad (BMO). The UK IMO Register offers a lot of historic information about the UK's participation in the IMO. Do browse the Leaders's Reports.
Related: United Kingdom Mathematics Trust (UKMT), a registered charity which conducts a number of mathematical enrichment activities via schools.  Uruguay
 USA
 Information on the USA Math Olympiad and the IMO.
 USA: AMC
 The American Mathematics Competitions (AMC).
 USA: USAMTS
 The USA Mathematical Talent Search (USAMTS) is a free mathematics competition open to any US middle or high school student. It is a great contest for students aspiring to Olympiad problem solving, since many of the problems require proofbased solutions.
Archives and Link Collections
 The IMO Collection =====NEW=====
 Here you will find a large collection of olympiad problems from all over the world. You will also find all the information regarding The IMO Compendium, the most complete collection of problems proposed to the International Mathematical Olympiads.
 The Art of Problem Solving
 The Art of Problem Solving contains a variety of resources for avid students of mathematics in middle and high school. There are many free resources (in addition to a Forum) such as articles, a LaTeX tutorial, and online Math Jam sessions. Olympiad problem solvers from all over the world participate in problem discussions. The site also sells a set of problem solving textbooks and has an online school.
Includes IMO Problems and Solutions, with authors.
 Mathematical Problem Solving Advice by Prof. Shapiro
 This website covers some general techniques for solving mathematical problems. It intends to grow into an interactive website. Maintained by Harold Shapiro.
 MathLinks.ro
 Math problem collections, a frequent (hard!) math contest, and a large problem solving community with many online formus for discussions. Maintained byValentin Vornicu.
 A Large Collection of Math Contest Material
 Includes Problems in Elementary Number theory (PEN), Topics in INequalities (TIN), and ProblemSolving WebDirectory (PSD). Archive maintained by Hojoo Lee(a.k.a. "ideahitme") in Republic of Korea.
 PEN: Problems in Elementary Number Theory
 A forum around the numbertheory problem collection of Hojoo Lee (see above).
 A Collection of MathOlympiadProblems
 Archive maintained by Hans Vernaeve (Hans.Vernaeve@rug.ac.be) in Belgium.
 Arkadii Slinko Mathematics Olympiad Site (gradually being transferred)
 Provides: a collection of problems, tutorials, training material, articles, a Monthly Internet Mathematics Olympiad, and information on the New Zealand Math Olympiads.
 Math Competitions Archive
 Kiran Kedlaya (MIT, USA, kray@post.com) has a Math Competitions Archive with some of the recent (back to 1991) IMO problem sets in various formats, and information about the USA Mathematical Olympiad (USAMO). He now has a separate Math Problem Directory.
 Math Competition on the Web
 Archive and links maintained by Naoki Sato (ensato@hotmail.com) in Toronto, Canada.
 OMAP: Online Math Problems
 Database of problems that appeared on various national and international math competitions around the world, including detailed info about the Putnam Math Competition. Maintained by meeroh@mit.edu.
 Soviet Union 19611986
 The problems of the AllSovietUnion national mathematical competitions (final part), 19611986 were translated into English and put on the Web by Vladimir Pertsel (voldemar@sagantec.co.il). There is also a plain ASCII version, and a compressed archive with everything: HTML, ASCII, and GIF pictures. [The original page and original archive are still available.]
 Olympiad Math Madness
 A collection of mathematical brainbusters, specially for those who are tired of notveryhard problems. Maintained by jefflock@geocities.com.
 Mathematics Olympiad Lecture Notes
 By Greg Gamble (gregg@maths.uwa.edu.au).
 20,000 Problems Under the Sea: Mathematical Treasures on the Web
 Online reference to mathematical problems.
 Kalva Homepage
 Problem collections maintained by John Scholes.
 Le Thai Hoang's Math Olympiad
 Le Thai Hoang's Math Olympiad Page contains many math problem sets, including shortlists for IMO from 1983 to 1998.
 Nick's Mathematical Puzzles
 A collection of puzzles ranging over geometry, probability, number theory, algebra, calculus, and logic. Hints are provided, along with answers, fully worked solutions, and links to related mathematical topics. Many of the puzzles are elementary in their statement, yet challenging. New puzzles are added on a regular basis.
 A key feature of the site is the detailed exposition, from first principles, of the puzzle solutions. Some of the puzzles are used to showcase particular mathematical concepts. See, for example, puzzle 56, which introduces a partition identity, and puzzle 63, where Ptolemy's Theorem permits a surprisingly simple solution. Further references are provided with many of the solutions.
Schools
Mathematics on WWW
 AIMS [ Activities Integrating Math & Science ]
 AMS [ American Mathematical Society ]
 EMS [ European Mathematical Society ]
 GAMS [ Guide to Available Mathematical Software ]
 IMU [ International Mathematical Union ]
 MAA [ Mathematical Association of America ]
 Math Archives
 PSTC [ Problem Solving Task Centres ]
 PSU [ Penn State University ]
 SIAM [ Society for Industrial and Applied Mathematics ]
Miscellaneous Links

 FAQ for newsgroup sci.math
 Eric Weisstein's World of Mathematics
 Equal Sums of Like Powers (investigations started by Chen Shuwen in 1986 while preparing for the Chinese Mathematics Olympiad) [European mirror]
 Paul Erdös info (the person and the number)
 Euclid's Elements (animated in Java)
 Fibonacci Numbers, Golden Section maintained by Ron Knott
 OnLine Mathematics Dictionary
 History of Mathematics
 MacTutor History of Mathematics Archive
 Interactive Mathematics Miscellany and Puzzles maintaned by Alexander Bogomolny (alexb@cuttheknot.com)
 Inverse Symbolic Calculator When you give this program an approximation to a real number, it will do its best to decide what that number `really' is. In essence, this is a greatly expanded online version of the Dictionary of Real Numbers by Borwein & Borwein (1990).
 The KnotPlot Site with/about (mathematical) knots
 Mathematical Fiction, references to works of fiction containing math
 Mathematical Quotations Server maintained by Mark Woodard (Mark.Woodard@furman.edu)
 Famous Unsolved Mathematical Problems at the Bingo Hideout Games Research
 The Math Forum
 The Mathematical Atlas
 This is MEGA Mathematics! by Los Alamos National Laboratory
 The Pi Pages
 The Prime Page
 Puzzles HQ Everything Puzzles, from 3d Puzzles to Zigsaw Puzzles.
 The Puzzler Web
 Random Number Generation
 Sloane's OnLine Encyclopedia of Integer Sequences
 Untangling the Mathematics of Knots
 UWELib: Mathematics
 W3C's Math Home Page
 WIMS  WWW Interactive Mathematics Server
 WWW Virtual Library: Mathematics