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Related papers: A bound on partitioning clusters

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Let $n > m\ge 2$ be integers and let $\mathcal{A}=\{A_1,\dots,A_m\}$ be a partition of $[n]=\{1,\dots,n\}$. For $X \subseteq [n]$, its $\mathcal{A}$-boundary region $\mathcal{A}(X)$ is defined to be the union of those blocks $A_i$ of…

Combinatorics · Mathematics 2019-06-21 Konrad Engel , Tran Dan Thu

We obtain a nontrivial bound on the number of solutions to the equation $A^{x_1} + A^{x_2} = A^{x_3} + A^{x_4}$, $1 \le x_1,x_2,x_3,x_4 \le \tau$, with a fixed $n\times n$ matrix $A$ over a finite field ${\mathbb F}_q$ of $q$ elements of…

Number Theory · Mathematics 2021-10-25 Alina Ostafe , Igor E. Shparlinski

We consider a simple model of a growing cluster of points in $\Re^d,d\geq 2$. Beginning with a point $X_1$ located at the origin, we generate a random sequence of points $X_1,X_2,\ldots,X_i,\ldots,$. To generate $X_{i},i\geq 2$ we choose a…

Probability · Mathematics 2025-01-08 Alan Frieze , Ravi Kannan , Wesley Pegden

We consider high-dimensional percolation at the critical threshold. We condition the origin to be disjointly connected to two points, $x$ and $x'$, and subsequently take the limit as $|x|$, $|x'|$ as well as $|x-x'|$ diverge to infinity.…

Probability · Mathematics 2025-06-10 Manuel Cabezas , Alexander Fribergh , Markus Heydenreich , Antal A. Járai

In nuclear cluster systems, a rigorous structural forbiddenness of virtual nuclear division into unexcited fragments is obtained. We re-analyze the concept of forbiddenness, introduced in Ref. 1 for the understanding of structural effects…

Nuclear Theory · Physics 2015-09-02 Huitzilin H. Yepez-Martinez , Peter Otto Hess

Typically clustering algorithms provide clustering solutions with prespecified number of clusters. The lack of a priori knowledge on the true number of underlying clusters in the dataset makes it important to have a metric to compare the…

Machine Learning · Computer Science 2018-11-20 Amber Srivastava , Mayank Baranwal , Srinivasa Salapaka

In 2003, Maroti showed that one could use the machinery of l-cores and l-quotients of partitions to establish lower bounds for p(n), the number of partitions of n. In this paper we explore these ideas in the case l=2, using them to give a…

Combinatorics · Mathematics 2007-05-23 Mark Wildon

Let $A$ be a subset of the cyclic group $\mathbf{Z}/p\mathbf{Z}$ with $p$ prime. It is a well-studied problem to determine how small $|A|$ can be if there is no unique sum in $A+A$, meaning that for every two elements $a_1,a_2\in A$, there…

Combinatorics · Mathematics 2023-09-20 Benjamin Bedert

We develop a simple and unified approach to investigate several aspects of the cluster statistics of random expansive (multi-)sets. In particular, we determine the limiting distribution of the size of the smallest and largest clusters, we…

Probability · Mathematics 2022-08-02 Konstantinos Panagiotou , Leon Ramzews

It is known that there are infinitely-many prime numbers which take the form of a polynomial of degree one with integer coefficients, this is Dirichlet's theorem. We use an elementary sieving argument together with bounds on the prime…

Number Theory · Mathematics 2017-07-24 Acquaah Peter

We adapt a number-theoretic technique of Yu to prove a purely analytic theorem: if f(x) is in L^1 and L^2, is nonnegative, and is supported on an interval of length I, then the supremum of the convolution f*f is at least 0.631 \| f \|_1^2 /…

Classical Analysis and ODEs · Mathematics 2010-03-04 Greg Martin , Kevin O'Bryant

Schur's partition theorem states that the number of partitions of n into distinct parts congruent 1, 2 (mod 3) equals the number of partitions of n into parts which differ by >= 3, where the inequality is strict if a part is a multiple of…

Combinatorics · Mathematics 2007-05-23 K. Alladi , A. Berkovich

We study statistical and computational limits of clustering when the means of the centres are sparse and their dimension is possibly much larger than the sample size. Our theoretical analysis focuses on the model $X_i = z_i \theta +…

Statistics Theory · Mathematics 2021-03-23 Matthias Löffler , Alexander S. Wein , Afonso S. Bandeira

We consider the {\em clustering with diversity} problem: given a set of colored points in a metric space, partition them into clusters such that each cluster has at least $\ell$ points, all of which have distinct colors. We give a…

Data Structures and Algorithms · Computer Science 2010-04-22 Jian Li , Ke Yi , Qin Zhang

We provide optimal upper bounds on the growth of iterated sumsets $hA=A+\dots+A$ for finite subsets $A$ of abelian semigroups. More precisely, we show that the new upper bounds recently derived from Macaulay's theorem in commutative algebra…

Commutative Algebra · Mathematics 2023-10-17 Shalom Eliahou , Eshita Mazumdar

The explosion in the amount of data available for analysis often necessitates a transition from batch to incremental clustering methods, which process one element at a time and typically store only a small subset of the data. In this paper,…

Machine Learning · Computer Science 2014-06-26 Margareta Ackerman , Sanjoy Dasgupta

Many clustering algorithms are guided by certain cost functions such as the widely-used $k$-means cost. These algorithms divide data points into clusters with often complicated boundaries, creating difficulties in explaining the clustering…

Machine Learning · Computer Science 2021-11-05 Moses Charikar , Lunjia Hu

We show that cluster algebras do not contain non-trivial units and that all cluster variables are irreducible elements. Both statements follow from Fomin and Zelevinsky's Laurent phenomenon. As an application we give a criterion for a…

Rings and Algebras · Mathematics 2013-05-10 Christof Geiß , Bernard Leclerc , Jan Schröer

Globular Clusters (GCs) have historically been subdivided in either two (disk/halo) or three (disk/inner-halo/outer-halo) groups based on their orbital, chemical and internal physical properties. The qualitative nature of this subdivision…

Astrophysics of Galaxies · Physics 2020-01-08 Mario Pasquato , Chul Chung

Those galaxy clusters which do not belong to the superclusters are referred to as the isolated clusters. Their relative abundance at a given epoch may be a powerful constraint of the dark energy equation of state since it depends strongly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Jounghun Lee