Results 41 to 50 of about 58,072 (195)
Forbidden intersection problems for families of linear maps
Discrete Analysis, 2023 Forbidden intersection problems for families of linear maps, Discrete Analysis 2023:19, 32 pp. A central problem in extremal combinatorics is to determine the maximal size of a set system given constraints on the sizes of the sets in the system and on ...
David Ellis, Guy Kindler, Noam Lifshitz
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A practical algorithm for weighted k‐hulls
Computer Graphics Forum, EarlyView.Abstract The convex hull is a central concept in computational geometry, geometry processing, and generally for summarizing sampled data. Its descriptive power suffers significantly in the presence of noise. The k‐hull, also known as the k‐depth contour in statistics, is the intersection of all half‐spaces that contain all but k data points, i.e. it is
N. Look, H. Meyer, M. Alexa
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Short Proofs of Some Extremal Results [PDF]
, 2013 We prove several results from different areas of extremal combinatorics, giving complete or partial solutions to a number of open problems. These results, coming from areas such as extremal graph theory, Ramsey theory and additive combinatorics, have ...
Sudakov, Benny +5 more
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Further results on permanents of Laplacian matrices of trees
Open MathematicsThe research on the permanents of graph matrices is one of the contemporary research topic in algebraic combinatorics. Brualdi and Goldwasser characterized the upper and lower bounds of permanents of Laplacian matrices of trees.
Wu Tingzeng, Dong Xiangshuai
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Discrete Analysis, 2020 An efficient container lemma, Discrete Analysis 2020:17, 56 pp. The hypergraph container lemma, discovered independently in 2012 by David Saxton and Andrew Thomason, and by József Balogh, Robert Morris and Wojciech Samotij, is an extremely powerful tool
Jozsef Balogh, Wojciech Samotij
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Gowers norms for automatic sequences
Discrete Analysis, 2023 Gowers norms for automatic sequences, Discrete Analysis 2023:4, 62 pp. There are several situations in additive and extremal combinatorics where it is useful to decompose an object $X$ into a "structured" part $S(X)$ and a "quasirandom" part $Q(X)$.
Jakub Byszewski +2 more
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On the Limits of Intransitive Coordination
Ratio, EarlyView.ABSTRACT A growing number of authors suggest that concept coordination—the kind of relation we pick out when we say that the concepts of one or more individuals represent something as the same—is not a transitive relation. Here we consider global features of representational systems to break new ground in the assessment of the intransitivity view. From
Víctor M. Verdejo, Joost J. Joosten
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Extremal combinatorics, iterated pigeonhole arguments, and generalizations of PPP
CoRR, 2022 We study the complexity of computational problems arising from existence theorems in extremal combinatorics. For some of these problems, a solution is guaranteed to exist based on an iterated application of the Pigeonhole Principle. This results in the definition of a new complexity class within TFNP, which we call PLC (for "polynomial long choice ...
Pasarkar, Amol +2 more
openaire +6 more sources
Dense H-free graphs are almost (Χ(H)-1)-partite [PDF]
, 2010 By using the Szemeredi Regularity Lemma, Alon and Sudakov recently extended the classical Andrasfai-Erdos-Sos theorem to cover general graphs. We prove, without using the Regularity Lemma, that the following stronger statement is true.
Peter Allen, Allen, Peter
core
Bounded exponential sums with multiplicative coefficients
Mathematika, Volume 72, Issue 4, October 2026.Abstract We investigate when the exponential sum Sf(x,α):=∑n⩽xf(n)e(nα)$S_f(x,\alpha) := \sum _{n\leqslant x}f(n)\mathrm{e}(n\alpha)$ is bounded, for a multiplicative function f$f$ and α∈R$\alpha \in \mathbb {R}$. We show that under natural assumptions, Sf(x,α)$S_f(x,\alpha)$ is bounded only when f$f$ is very close to a twisted Dirichlet character χ(n ...
Péa Bazin, Ihor Pylaiev, Fred Tyrrell
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