21. Math: Equations And Symbols Outside of the religioastronomical sphere, only the problems of day to day life(such as purchasing and bartering) interested the indian mathematicians. next. http://www.gosai.com/chaitanya/saranagati/html/vishnu_mjs/math/math_5.html

Previous Next Math Index Articles Index ... Vedic Age Equations and Symbols B.B. Dutta writes: "The use of symbols-letters of the alphabet to denote unknowns, and equations are the foundations of the science of algebra. The Hindus were the first to make systematic use of the letters of the alphabet to denote unknowns. They were also the first to classify and make a detailed study of equations. Thus they may be said to have given birth to the modern science of algebra." The great Indian mathematician Bhaskaracharya (1150 C.E.) produced extensive treatises on both plane and spherical trigonometry and algebra, and his works contain remarkable solutions of problems which were not discovered in Europe until the seventeenth and eighteenth centuries. He preceded Newton by over 500 years in the discovery of the principles of differential calculus. A.L. Basham writes further, "The mathematical implications of zero (sunya) and infinity, never more than vaguely realized by classical authorities, were fully understood in medieval India. Earlier mathematicians had taught that X/0 = X, but Bhaskara proved the contrary. He also established mathematically what had been recognized in Indian theology at least a millennium earlier: that infinity, however divided, remains infinite, represented by the equation oo /X = oo." In the 14th century, Madhava , isolated in South India, developed a power series for the arc tangent function, apparently without the use of calculus, allowing the calculation of pi to any number of decimal places (since arctan 1 = pi/4). Whether he accomplished this by inventing a system as good as calculus or without the aid of calculus; either way it is astonishing.

22. Math: Evolution Of Roman Numerals From India Medieval indian mathematicians, such as Brahmagupta (seventh century), Mahavira (ninthcentury), and Bhaskara (twelfth century), made several discoveries which http://www.gosai.com/chaitanya/saranagati/html/vishnu_mjs/math/math_4.html

Previous Next Math Index Articles Index ... Vedic Age Evolution of Arabic (Roman) Numerals from India A close investigation of the Vedic system of mathematics shows that it was much more advanced than the mathematical systems of the civilizations of the Nile or the Euphrates. The Vedic mathematicians had developed the decimal system of tens, hundreds, thousands, etc. where the remainder from one column of numbers is carried over to the next. The advantage of this system of nine number signs and a zero is that it allows for calculations to be easily made. Further, it has been said that the introduction of zero, or sunya as the Indians called it, in an operational sense as a definite part of a number system, marks one of the most important developments in the entire history of mathematics. The earliest preserved examples of the number system which is still in use today are found on several stone columns erected in India by King Ashoka in about 250 B.C.E. Similar inscriptions are found in caves near Poona (100 B.C.E.) and Nasik (200 C.E.). These earliest Indian numerals appear in a script called brahmi After 700 C.E. another notation, called by the name "Indian numerals," which is said to have evolved from the brahmi numerals, assumed common usage, spreading to Arabia and from there around the world. When Arabic numerals (the name they had then become known by) came into common use throughout the Arabian empire, which extended from India to Spain, Europeans called them "Arabic notations," because they received them from the Arabians. However, the Arabians themselves called them "Indian figures" (Al-Arqan-Al-Hindu) and mathematics itself was called "the Indian art" (hindisat).

23. HS2481 B) decimal place value. Around 600 indian mathematicians dropped the oldernumber systems in favour of nine symbols only. Two indian mathematicians. http://www.chstm.man.ac.uk/people/agar/hs248_31.htm

course page CHSTM homepage HS2481, Week 3 Slot 1 1) Chinese Mathematics 2) Indian Mathematics Chinese Civilisation Mythical origins c3000 BC But earliest archaeological evidence is 1,600 BC for the Shang Dynasty Zhou Dynasty, c1000BC Period of warring feudal states intellectually fertile, 6th C BC eg Confucius Unification under Emperor Qin Shi Huangchi, 221 BC, followed by Han Dynasty (up to 3rd C AD) highly centralised bureaucracy (entry by exam, not birth) eg standard taxes, law, weights, measures, money, written script Han Mathematical Texts 1) Zhoubi suanjing ("Arithmetical Classic of the Gnomon and the Circular Paths of Heaven") 2) Jiuzhang suanshu ("Nine Chapters on the Mathematical Art") compiled under Han, but parts date to Zhou Dynasty 246 problems on surveying, agriculture, commerce, engineering, taxation, calculation, solutions of equations, right angles sets of specific problems (like Babylonian) rather than logically ordered treatise (like Greeks) compare to guiding philosophy of Confucianism: pragmatic, didactic Number Notation 1) Multiplicative System based on powers of 10 eg 2) Counting Board see handout zero was marked by a gap (until 13th C when "0" was used) Red rods for positive numbers Black rod for negative numbers rods "flying so quickly that the eye could not follow their movement" Later the counting board gave way to the Abacus (14th Century?)

24. The Arab-Indian Contribution. the inheritance of the Egyptian and Babylonian cultures merged with the texts ofclassic Greek geometry and the innovations of indian mathematicians, the Arabs http://www.math.unifi.it/archimede/archimede_inglese/trigonometria/trigonometria

The Garden of Archimedes A Museum for Mathematics Brief history of trigonometry The Arab-Indian contribution The Roman conquest didn't contribute in any way to the development of the mathematical sciences but neither did it hinder its continuation, especially around the school of Alexandria that continued on well beyond the Roman conquest of Egypt in the first century B.C. After the fall of the Western Roman Empire, and cultural retreat of the Eastern one, the natural successors of the Greek geometers - at least from the IX century - were the Arabs. Placed at the crossroads of a mathematical tradition in which the inheritance of the Egyptian and Babylonian cultures merged with the texts of classic Greek geometry and the innovations of Indian mathematicians, the Arabs quickly assimilated most of these different traditions. This they incorporated into an original method, that a few centuries later, they bequeathed to the scholars of an emerging Europe. Some fundamental discoveries, both technological and on paper, reached the West through Arab influence, and were to be crucial in the diffusion of culture and the development of science. These are both scientific, like the use of the numeric characters commonly called Arab (which would more accurately be called Indian), and the positional notation. The first innovation related to Alexandrine trigonometry came from India: the use of the sine instead of the chord. The first work containing the table of the sines, which dates from the IV or V century of our era, is known by the name of

25. Numbersystem, Some Clarification: Interact Inn All India Mailing List English. Yes, it is a fact that indian mathematicians developed thenumber system in the pre Greek/Roman era. The conceptualisation http://manaskriti.com/InteractInn/10119801.html

Recent Discussions Numbersystem, some clarification 10th Nov 1998 Kailash Srivastava @mail.bip.net 10th Nov 1998 Vivek Murarka @manaskriti.com 12th Nov 1998 vijay @wmi.co.in 12th Nov 1998 Aditya, the Hindu Skeptic @bc.seflin.org 13th Nov 1998 Kerry R Kinchen @stic.net 15th Nov 1998 Vivek Murarka @manaskriti.com 16th Nov 1998 P srini @hotmail.com

26. Panchangam: Hindu Calendar-http://mailerindia.com. of 30 (from Greek Deca). While, as early as 100 BCE indian mathematicianshad exact names for figures upto 10 to the power of 53. http://mailerindia.com/cgi-bin/main.cgi?astroin

27. Hindu1 More importantly, indian mathematicians knew algebra at least as early as the 5thcentury AD Known as Bijaganitam, algebra (a corruption of the Arabic word Al http://www.geocities.com/avarangal/hindu1.html

forwarded message[ Forwarded to tamil.net by Bala] Date: Wed, 05 Jan 2000 05:41:33 GMT - From: Mo24680@cs.com - Newsgroups: soc.culture.indian, soc.culture.pakistan, - alt.religion.islam, soc.culture.usa Subject: Hindus discovered everything in Mathematics. Ambati M Rao, Jayakrishna Ambati, Balamurali K Ambati, Gomathi S Rao 'In science, more than in any other human institution, it is necessary to search out the past in order to understand the present and to control the future.' J D Bernal, Science in History As we hurtle into a new millennium, we would do well to reflect where all those s came from. The greatness that was Greece and the grandeur that was Rome started their numeral systems at one. The Arabs brought the modern numerals, including zero, to Europe centuries ago. But while , are commonly and mistakenly referred to as the "Arabic" numerals, they actually originated in India, and are but one of many achievements that became treasures lost to the oblivion of history. India is the epitome of diversity in all respects, geographically and culturally. From such diversity has bloomed the myriad blossoms of science and mathematics. Indian science flowered long before the classical age of Europe and flourishes to this day. .

28. I Love Maths -A Complete, Indian Site On Maths Maths Club has lots of fun, humor (humour), jokes, puzzles, a Maths quotient test(do try it!), a section on ancient indian mathematicians (like Aryabhata http://www.geocities.com/madanlalaggarwal/ilovemaths.htm

www.ilovemaths.com - A complete, Indian site on school math. Covers cbse, icse, isc. Fun, humor, jokes and puzzles, vedic maths, ancient India famous mathematicians. Mathclubs. Lesson plans, questions, problems, exercises, worksheets in mathematics. Maths Club has lots of fun, humor (humour), jokes, puzzles, a Maths quotient test (do try it!), a section on ancient Indian Mathematicians (like Aryabhata, Bhaskara, Ramanujan etc.), some real gems from Leelavati, history of mathematics and so on. "We Recommend" section has many useful links to sites related to Math. There is a collection of interesting articles like different kinds of numbers (prime numbers, square numbers, palindromes etc), story of zero, story of pi( Professor Theta is a multi featured question answering service. Anybody can post a question (mainly from 6th to 12th standard level) and anybody can reply. If nobody replies, professor Theta will attempt it. Homework help (helper) is at hand! Vedic Maths : You will be proud to be an Indian! At present we have covered only the multiplication sutra from vedic mathematics.

29. Pure Cubic for solving the equation. Bhaskara was somewhat of a poet as weremany indian mathematicians at this time. Here are a couple of http://hem.passagen.se/ceem/india.htm

Solving the Pure Cubic There is no evidence that the following method for solving the cube was known earlier than Aryabhata (500 BC). It is stanza 5 of his Aryabhatiya that tells of this method: One should divide the second aghana by three times the square of the cube roots of the preceeding ghana. The square (of the quotient) multiplied by three times the purva (that part of the cube root already found) is to be subtracted from the first aghana and the cube (of the quotient of the above division) is to be subtracted from the ghana. Certain steps have been left out in Aryabhata's method for calculating the cube root. This may have been due to limitations of the Sanscrit language. It was common at this time to pass on teachings orally, hence, it is understandable that some written methods may be vague. Here is an example of how Aryabhata solved the cube, taken from W.E. Clark: Aryabhatiya (Chicago University Press), 1930. Find the cube of 1860867. Counting from right to left, the first, fourth, seventh and so on places are named ghana(cubic), the second, fifth, eighth and so on are called the first aghana (noncubic), while the third, sixth, ninth places and so on are called the second aghana. So in this example we start by taking the cube root of 1=1 1-1=0, and you bring down the 8.

30. Patrika For their contacts and influences on indian mathematicians he also covered GHHardy, Andre Weil and the inspiring Jesuit priest and teacher Rev. Fr. http://www.ias.ac.in/patrika/patrika37/patrika37.html

No. 37 March 2003 Newsletter of the Indian Academy of Sciences 2002 Annual meeting 8-10 November 2002, Chandigarh The Panjab University invited the Academy to hold its 2002 annual meeting in Chandigarh. This meeting, sixty-eighth in the series, was held from 8 to 10 November 2002. It was attended by over 120 fellows and associates and 30 invited teachers from outside Chandigarh and a large number of students and researchers from within. The inaugural session was held at the university auditorium on the forenoon of 8 th . The University Vice-Chancellor K.N. Pathak welcomed the audience and this was followed by the traditional introduction of Fellows by the President of the Academy K. Kasturirangan. Kasturirangan then delivered his scientific address. K. Kasturirangan In his address Kasturirangan traced the emergence of X-ray astronomy as a new tool to study the universe in a hitherto unexplored part of the electromagnetic spectrum. Recent advances in instrumentation and space technology have made thisfield a full-fledged component of astronomy, especially able to probe strong gravitational and magnetic fields and regions of very high matter density. A large number of X-ray sources, including accreting compact objects, have been studied in detail.He related these developments to the proposed 2006 launch of India's first dedicated astronomical satellite, ASTROSAT, which will offer unique capabilities all the way from optical and UV to hard X-ray energies.

31. ISHM | Ganita Bharati | Contents WAZIR HASAN ABDI Some Works of indian mathematicians Who Wrote in Persian69. RC GUPTA indian mathematicians abroad up to the 10th Century 10-16. http://www.indianshm.com/ganitabharati/toc/show.php?id=000056

32. | International School Of Photonics | ISP Knowledge Portal | Great Indian Scient replication in laboratory, is a step towards the creation of life artificially.indian mathematicians. Top of the pageTop of the page 2. http://www.photonics.cusat.edu/Indian_scientists2.html

Homi Jehangir Bhabha Find more ... Dr. Homi Jehangir Bhabha Vikram Sarabhai Find more ... Dr. Vikram A Sarabhai Prof. S. S. Bhatnagar Find more ... Prof. Shanti Swarup Bhatnagar P. C. Ray Find more ... Acharya Prafulla Chandra Ray Dr. Hargovind Khorana Find more ... Dr. Hargovind Khorana Indian Mathematicians Top of the page

33. KUVIYAM-English - Technology Renaissance. Probably the most celebrated indian mathematicians belongingto this period was Aaryabhat.a, who was born in 476 CE. http://www.kuviyam.com/b001r06/tech.htm

Vedic Altars and the :::Pythagorean theorem::: Zero and the Place Value System Luminaries of Classical Indian Mathematics- Aryabhata Vedic Altars and the :::Pythagorean theorem::: Zero and the Place Value System Far more important to the development of modern mathematics than either Greek or Indian geometry was the development of the place value system of enumeration, the base ten system of calculation which uses nine numerals and zero to represent numbers ranging from the most minuscule decimal to the most inconceivably large power of ten. This system of enumeration was not developed by the Greeks, whose largest unit of enumeration was the myriad (10,000) or in China, where 10,000 was also the largest unit of enumeration until recent times. Nor was it developed by the Arabs, despite the fact that this numeral system is commonly called the Arabic numerals in Europe, where this system was first introduced by the Arabs in the thirteenth century. Rather, this system was invented in India, where it evidently was of quite ancient origin. The Yajurveda Samhitaa, one of the Vedic texts predating Euclid and the Greek mathematicians by at least a millennium, lists names for each of the units of ten up to 10 to the twelfth power (paraardha). (Subbarayappa 1970:49) Later Buddhist and Jain authors extended this list as high as the fifty-third power, far exceeding their Greek contemporaries, who lacking a system of enumeration were unable to develop abstract mathematical concepts.

34. ThinkQuest : Library : Mathematics History They also used decimal system. indian mathematicians thought aboutthe negative numbers for the first time and they made it a rule. http://library.thinkquest.org/22584/emh1300.htm

Index Math Mathematics History An extensive history of mathematics is at your fingertips, from Babylonian cuneiforms to advances in Egyptian geometry, from Mayan numbers to contemporary theories of axiomatical mathematics. You will find it all here. Biographical information about a number of important mathematicians is included at this excellent site. Visit Site 1998 ThinkQuest Internet Challenge Languages English Korean Students Hyun-jin Jae-yun Hwang(Seoul Yo Sang), Kwan-ak Gu, Korea, South Kyung-sun Jae-yun Hwang(Seoul Yo Sang), Kwan-ak Gu, Korea, South So-young Jae-yun Hwang(Seoul Yo Sang), Kwan-ak Gu, Korea, South Coaches Jae-yun Jae-yun Hwang(Seoul Yo Sang), Kwan-ak Gu, Korea, South Jong-hyun Jong-hyun Lee(Seoul Yo Sang), Kwan-ak Gu, Korea, South Dea-won Dea-won Ko (Seoul Yo Sang), Kwan-ak Gu, Korea, South Want to build a ThinkQuest site? The ThinkQuest site above is one of thousands of educational web sites built by students from around the world. Click here to learn how you can build a ThinkQuest site.

35. Vedic Mathematics that the numeral 0 was indeed the creation of indian mathematicians. Introductionof zero brought about a new revolution into the world of mathematics. http://www.cs.uml.edu/~asaxena/vedic-maths.html

Vedic - Mathematics This interesting article was forwarded by a friend. I wanted to share this with you. Mathematics is the queen of subjects. Rightly so, then, Vedic Mathematics is the glowing crown that adorns its proud forehead. Very few of the masses today are aware today, of Vedic mathematics, the magnanimity of its profound implications, and of its origins which guided the rest of the world towards purer and more intricate branches of mathematics and which, laid the foundations for number theory and arithmetic, the teeny-weeny part of which we are taught during our alma-mater days with hardly any reference made to its rightful owners ? our very own ancestors ?who pursued the study of mathematics with no less finesse than that of a fine art. A well-known fact it is, as every one knows now, for he/she has seen himself/herself or his friend, being answered by his teacher, during the primary years of his education, in response to his/her query full of childish criticism “What has India given to Mathematics? that the numeral was indeed the creation of Indian mathematicians. Introduction of zero brought about a new revolution into the world of mathematics. It was zero that gave rise to the idea of representing numbers using base 10, as it is commonly used today. And it is zero because of which you are able to read this article. But why? How would a computer work without zeros and ones!!! So that’s the zero there, right! Though the Arabs are given the credit of taking mathematics into broader frontiers, they had begun their work with the help of Indian manuscripts. The story goes something like this. It was in 773 that the Arabs were able to set their eyes on the astounding developments of numerical methods Indians used when one of the Indian palmist and fortune-teller happened to visit the Arabian lands. So impressed were the Arab mathematicians with Indian inventions that the Arab mathematician Muhammed-Ibna-Musa-Abu-Jafar-Al-Khwarizmi himself came to India to study Indian mathematics. After stating here for some time after learning the subjects to his satisfaction, he wrote his manuscript “Algebra ’–b-e-Mukabla? This is how ‘Algebra?was born. His works, which were nothing but a translation of his Indian studies, left the European mathematicians spell-bound, especially by the use of base 10 to represent numbers. The idea of representing numbers by base 10, is thus, originally Indian.

36. Mathematics While the first steps had already been taken by Euclid in the third centuryBC, it was the indian mathematicians who furthered the knowledge. http://www.indiaheritage.com/science/math.htm

A Living portrait of India India Heritage Science Mathematics A s early as the Vedic period (1500-1000BC), the Shulvasutras facilitated the construction of sacrificial altars by their principles of plane geometry particularly through the figures of the triangle and the rectangle, the circle and the rhombus. Negative numbers, the zero, place-value notations and simple algorithms were already a part of mathematics. The great Indian mathematician Aryabhata (born 476 AD) wrote the Aryabhatiya - a volume of 121 verses. Apart from discussing astronomy, he laid down procedures of arithmetic, geometry, algebra and trigonometry. He calculated Pi at 3.1416 and covered subjects like numerical squares and cube roots. Aryabhata is credited with the emergence of trigonometry through sine functions. The eleventh century saw the solving of Diophantine equations (second order), and by the fourteenth century tremendous progress had been made in trigonometry. Sine and cosine functions as well as high-level approximations were tabulated and the essential irrationality of trigonometry recognized. Around the beginning of the sixteenth century Madhava developed his own system of calculus based on his knowledge of trigonometry. He was an untutored mathematician from Kerala, and preceded Newton and Liebnitz by more than a century.

37. Science Line - Mathematics & Computing - Can The Value Of (pi) Ever Change? By the early 6th century Chinese and indian mathematicians had independentlyconfirmed or improved the number of decimal places. http://www.sciencenet.org.uk/database/mathcomp/mathematics/m00053d/m00053d.html

Can the value of (pi) ever change? No. In mathematics, the symbol denotes the ratio of the circumference of a circle to its diameter. The ratio is approximately 3.14159265, pi being an irrational number (one that cannot be expressed as a simple fraction or as a decimal with a finite number of decimal places) and a transcendental number (one without continuously recurrent digits). Electronic computers in the late 20th century have carried pi to more than 200 billion decimal places. Pi occurs in various mathematical calculations. The circumference (c) of a circle can be determined by multiplying the diameter (d) by c = d The area (A) of a circle is determined by the square of the radius (r): A = r The only way pi can change is by the accuracy to which it is calculated. In very ancient times, 3 was used as the approximate value of pi, and not until Archimedes (3rd century BC) does there seem to have been a scientific effort to compute it; he reached a figure equivalent to about 3.14. A figure equivalent to 3.1416 dates from before AD 200. By the early 6th century Chinese and Indian mathematicians had independently confirmed or improved the number of decimal places. By the end of the 17th century in Europe, new methods of mathematical analysis provided various ways of calculating . Early in the 20th century the Indian mathematical genius Srinivasa Ramanujan developed ways of calculating that were so efficient that they have been incorporated into computer algorithms, permitting expressions of in millions of digits.

38. The Hindu : Why Indian Science Scores indian mathematicians invented negative numbers the British mathematician LancelotHogben, grudgingly acknowledging this, suggested ungraciously that perhaps http://www.thehindu.com/thehindu/mag/2003/06/08/stories/2003060800310300.htm

Online edition of India's National Newspaper Sunday, Jun 08, 2003 Group Publications Business Line The Sportstar Frontline The Hindu About Us Contact Us Magazine Published on Sundays Features: Magazine Literary Review Life Metro Plus ... Magazine Why Indian science scores And yet the roots of Indian science and technology go far deeper than Nehru. I was reminded of this yet again by a remarkable new book, Lost Discoveries , by the American writer Dick Teresi. Teresi's book studies the ancient non-Western foundations of modern science, and while he ranges from the Babylonians and Mayans to Egyptians and other Africans, it is his references to India that caught my eye. And how astonishing those are! The Rig Veda asserted that gravitation held the universe together 24 centuries before the apple fell on Newton's head. The Vedic civilisation subscribed to the idea of a spherical earth at a time when everyone else, even the Greeks, assumed the earth was flat. By the Fifth Century A.D. Indians had calculated that the age of the earth was 4.3 billion years; as late as the 19th Century, English scientists believed the earth was a hundred million years old, and it is only in the late 20th Century that Western scientists have come to estimate the earth to be about 4.6 billion years old. If I were to focus on just one field in this column, it would be that of mathematics. India invented modern numerals (known to the world as "Arabic" numerals because the West got them from the Arabs, who learned them from us!). It was an Indian who first conceived of the zero

39. INDIAN MATHEMATICS (Web Pages) By Antreas P. Hatzipolakis Srinivasa Ramanujan Aiyanga URL http//home.att.net/~sprasad/math.htm NoteBiographies of other indian mathematicians at St Andrews Archive http//www http://mathforum.org/epigone/math-history-list/skixvoxspoi

INDIAN MATHEMATICS (Web Pages) by Antreas P. Hatzipolakis reply to this message post a message on a new topic Back to math-history-list Subject: INDIAN MATHEMATICS (Web Pages) Author: xpolakis@hol.gr Date: Thu, 28 May 1998 22:22:58 +0200 INDIAN MATHEMATICS Vedic Mathematics URL1: http://www.jiva.org/observe/vedicmat/vedicmat.html http://www.silverleaf.com/jiva/observe/vedicmat/vedicmat.html Swami B. B. Visnu: Mathematics and the Spiritual Dimension URL: http://www.gosai.com/chaitanya/vishnu_mj/articles/math/index.html Ramesh Mahadevan: Easy as PI (Based on true incidents) URL: http://www.image-in-asian.com/ramesh_m/ramesh10.html Krishna Kunchithapadam: Extracting the digits of pi from the SlOka http://www.cs.wisc.edu/~krisna/misc/pi.html Meera Nanda: The Science Wars in India URL: http://www.astro.queensu.ca/~bworth/Reason/Sokal/Commentary/nanda.html Excerpt: Hindu nationalists have heeded the call for "decolonizing" science, and responded with aggressive propaganda for "Hindu ways of knowing," which they present as the locally embedded alternative to the alien and colonizing Western science. The two examples of the right's "Hinduization" of science and politics that I will discuss - - the introduction of Vedic mathematics in public schools and the spread of "Vastu shastra" (ancient Indian material science) - - do indeed meet the criteria of decolonized science advocated by left theorists: both are opposed to "Eurocentric Northern" ways of knowing; both are "situated knowledges" of non-Western people. Joseph's Discussion of the Sriyantra URL:

40. [HM] Project On Indian Mathematics By Jean Michel Delire with other sources (Chapter 2), analysed the contribution of its commentators, especiallyDvaarakaanaatha who quoted classic indian mathematicians and heavily http://mathforum.org/epigone/historia/longimpdwor

[HM] Project on Indian mathematics by Jean Michel Delire reply to this message post a message on a new topic Back to historia Subject: [HM] Project on Indian mathematics Author: jmdelire@ulb.ac.be Date: The Math Forum

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