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Zero-sum Problem
In number theory, zero-sum problems are certain kinds of combinatorial problems about the structure of a finite abelian group. Concretely, given a finite abelian group ''G'' and a positive integer ''n'', one asks for the smallest value of ''k'' such that every sequence of elements of ''G'' of size ''k'' contains ''n'' terms that sum to 0. The classic result in this area is the 1961 theorem of Paul Erdős, Abraham Ginzburg, and Abraham Ziv. They proved that for the group \mathbb/n\mathbb of integers modulo ''n'', k = 2n - 1. Explicitly this says that any multiset of 2''n'' − 1 integers has a subset of size ''n'' the sum of whose elements is a multiple of ''n'', but that the same is not true of multisets of size 2''n'' − 2. (Indeed, the lower bound is easy to see: the multiset containing ''n'' − 1 copies of 0 and ''n'' − 1 copies of 1 contains no ''n''-subset summing to a multiple of ''n''.) This result is known as the Erdős–Ginzburg–Ziv theorem after its discovere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Number Theory
Number theory (or arithmetic or higher arithmetic in older usage) is a branch of pure mathematics devoted primarily to the study of the integers and arithmetic function, integer-valued functions. German mathematician Carl Friedrich Gauss (1777–1855) said, "Mathematics is the queen of the sciences—and number theory is the queen of mathematics."German original: "Die Mathematik ist die Königin der Wissenschaften, und die Arithmetik ist die Königin der Mathematik." Number theorists study prime numbers as well as the properties of mathematical objects made out of integers (for example, rational numbers) or defined as generalizations of the integers (for example, algebraic integers). Integers can be considered either in themselves or as solutions to equations (Diophantine geometry). Questions in number theory are often best understood through the study of Complex analysis, analytical objects (for example, the Riemann zeta function) that encode properties of the integers, primes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kemnitz's Conjecture
In additive number theory, Kemnitz's conjecture states that every set of lattice points in the plane has a large subset whose centroid is also a lattice point. It was proved independently in the autumn of 2003 by Christian Reiher, then an undergraduate student, and Carlos di Fiore, then a high school student. The exact formulation of this conjecture is as follows: :Let n be a natural number and S a set of 4n-3 lattice points in plane. Then there exists a subset S_1 \subseteq S with n points such that the centroid of all points from S_1 is also a lattice point. Kemnitz's conjecture was formulated in 1983 by Arnfried Kemnitz as a generalization of the Erdős–Ginzburg–Ziv theorem In number theory, zero-sum problems are certain kinds of combinatorial problems about the structure of a finite abelian group. Concretely, given a finite abelian group ''G'' and a positive integer ''n'', one asks for the smallest value of ''k'' suc ..., an analogous one-dimensional result stating that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zhi-Wei Sun
Sun Zhiwei (, born October 16, 1965) is a Chinese mathematician, working primarily in number theory, combinatorics, and group theory. He is a professor at Nanjing University. Biography Sun Zhiwei was born in Huai'an, Jiangsu. Sun and his twin brother Sun Zhihong proved a theorem about what are now known as the Wall–Sun–Sun primes. Sun proved Sun's curious identity in 2002. In 2003, he presented a unified approach to three topics of Paul Erdős in combinatorial number theory: covering systems, restricted sumsets, and zero-sum problem In number theory, zero-sum problems are certain kinds of combinatorial problems about the structure of a finite abelian group. Concretely, given a finite abelian group ''G'' and a positive integer ''n'', one asks for the smallest value of ''k'' suc ...s or EGZ Theorem. With Stephen Redmond, he posed the Redmond–Sun conjecture in 2006. In 2013, he published a paper containing many conjectures on primes, one of which states that for any ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Springer-Verlag
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing. Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in the 1990s and a sale to venture capitalists it fused with Wolters Kluwer and eventually became part of Springer Nature in 2015. Springer has major offices in Berlin, Heidelberg, Dordrecht, and New York City. History Julius Springer founded Springer-Verlag in Berlin in 1842 and his son Ferdinand Springer grew it from a small firm of 4 employees into Germany's then second largest academic publisher with 65 staff in 1872.Chronology ". Springer Science+Business Media. In 1964, Springer expanded its business internationally, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graduate Texts In Mathematics
Graduate Texts in Mathematics (GTM) (ISSN 0072-5285) is a series of graduate-level textbooks in mathematics published by Springer-Verlag. The books in this series, like the other Springer-Verlag mathematics series, are yellow books of a standard size (with variable numbers of pages). The GTM series is easily identified by a white band at the top of the book. The books in this series tend to be written at a more advanced level than the similar Undergraduate Texts in Mathematics series, although there is a fair amount of overlap between the two series in terms of material covered and difficulty level. List of books #''Introduction to Axiomatic Set Theory'', Gaisi Takeuti, Wilson M. Zaring (1982, 2nd ed., ) #''Measure and Category – A Survey of the Analogies between Topological and Measure Spaces'', John C. Oxtoby (1980, 2nd ed., ) #''Topological Vector Spaces'', H. H. Schaefer, M. P. Wolff (1999, 2nd ed., ) #''A Course in Homological Algebra'', Peter Hilton, Urs Stammbac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
József Solymosi
József Solymosi is a Hungarian-Canadian mathematician and a professor of mathematics at the University of British Columbia. His main research interests are arithmetic combinatorics, discrete geometry, graph theory, and combinatorial number theory. Education and career Solymosi earned his master's degree in 1999 under the supervision of László Székely from the Eötvös Loránd University and his Ph.D. in 2001 at ETH Zürich under the supervision of Emo Welzl. His doctoral dissertation was ''Ramsey-Type Results on Planar Geometric Objects''. From 2001 to 2003 he was S. E. Warschawski Assistant Professor of Mathematics at the University of California, San Diego. He joined the faculty of the University of British Columbia in 2002. He was editor in chief of the ''Electronic Journal of Combinatorics'' from 2013 to 2015. Contributions Solymosi was the first online contributor to the first Polymath Project, set by Timothy Gowers to find improvements to the Hales–Jewett theo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subset Sum Problem
The subset sum problem (SSP) is a decision problem in computer science. In its most general formulation, there is a multiset S of integers and a target-sum T, and the question is to decide whether any subset of the integers sum to precisely T''.'' The problem is known to be NP. Moreover, some restricted variants of it are NP-complete too, for example: * The variant in which all inputs are positive. * The variant in which inputs may be positive or negative, and T=0. For example, given the set \, the answer is ''yes'' because the subset \ sums to zero. * The variant in which all inputs are positive, and the target sum is exactly half the sum of all inputs, i.e., T = \frac(a_1+\dots+a_n) . This special case of SSP is known as the partition problem. SSP can also be regarded as an optimization problem: find a subset whose sum is at most ''T'', and subject to that, as close as possible to ''T''. It is NP-hard, but there are several algorithms that can solve it reasonably quickly in pra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Davenport Constant
Davenport may refer to: Places Australia *Davenport, Northern Territory, a locality * Hundred of Davenport, cadastral unit in South Australia **Davenport, South Australia, suburb of Port Augusta **District Council of Davenport, former local government area near Port Augusta **Corporate Town of Davenport, former local government municipality near Port Augusta *Electoral district of Davenport, in South Australia Canada *Davenport (electoral district), a federal electoral district *Davenport (provincial electoral district), in Ontario *Davenport, Toronto, a neighbourhood and former village in Toronto *Davenport Road, Toronto United Kingdom * Davenport, Cheshire *Davenport, Greater Manchester United States * Davenport, Iowa, the largest city of that name in the US *Davenport, California *Davenport, Florida * Davenport, Nebraska *Davenport, New York **Davenport Center, New York * Davenport, North Dakota *Davenport, Oklahoma *Davenport, Virginia *Davenport, Washington *Davenport Creek, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David J
David John Haskins (born 24 April 1957, Northampton, Northamptonshire, England), better known as David J, is a British alternative rock musician, producer, and writer. He is the bassist for the gothic rock band Bauhaus and for Love and Rockets. He has composed the scores for a number of plays and films, and also wrote and directed his own plays, ''Silver for Gold (The Odyssey of Edie Sedgwick)'', in 2008, which was restaged at REDCAT in Los Angeles in 2011, and ''The Chanteuse and The Devil's Muse'' in 2011. His artwork has been shown in galleries internationally, and he has been a resident DJ at venues such as the Knitting Factory. David J has released a number of singles and solo albums, and in 1990 he released one of the first No. 1 hits on the then nascent Modern Rock Tracks charts, with "I'll Be Your Chauffeur". His most recent single, "The Day That David Bowie Died" entered the UK vinyl singles chart at number 4 in 2016. The track appears on his double album, ''Vaga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weighted EGZ Theorem
A weight function is a mathematical device used when performing a sum, integral, or average to give some elements more "weight" or influence on the result than other elements in the same set. The result of this application of a weight function is a weighted sum or weighted average. Weight functions occur frequently in statistics and analysis, and are closely related to the concept of a measure. Weight functions can be employed in both discrete and continuous settings. They can be used to construct systems of calculus called "weighted calculus" and "meta-calculus".Jane Grossma''Meta-Calculus: Differential and Integral'' , 1981. Discrete weights General definition In the discrete setting, a weight function w \colon A \to \R^+ is a positive function defined on a discrete set A, which is typically finite or countable. The weight function w(a) := 1 corresponds to the ''unweighted'' situation in which all elements have equal weight. One can then apply this weight to various conce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christian Reiher
Christian Reiher (born 19 April 1984 in Starnberg) is a German mathematician. He is the fifth most successful participant in the history of the International Mathematical Olympiad, having won four gold medals in the years 2000 to 2003 and a bronze medal in 1999. Just after finishing his '' Abitur'', he proved Kemnitz's conjecture, an important problem in the theory of zero-sums. He went on to earn his Diplom in mathematics from the Ludwig Maximilian University of Munich. Reiher received his Dr. rer. nat. from the University of Rostock under supervision of in February 2010 (Thesis: ''A proof of the theorem according to which every prime number possesses property B'') and works now at the University of Hamburg The University of Hamburg (german: link=no, Universität Hamburg, also referred to as UHH) is a public research university in Hamburg, Germany. It was founded on 28 March 1919 by combining the previous General Lecture System ('' Allgemeines Vo .... Selected pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
