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Related papers: Erasure codes and Tur\'an hypercube problems

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Recently, locally repairable codes (LRCs) with local erasure correction constraints that are unequal and disjoint have been proposed. In this work, we study the same topic and provide some improved and additional results.

Information Theory · Computer Science 2017-04-10 Geonu Kim , Jungwoo Lee

We investigate natural Tur\'an problems for mixed graphs, generalizations of graphs where edges can be either directed or undirected. We study a natural \textit{Tur\'an density coefficient} that measures how large a fraction of directed…

Combinatorics · Mathematics 2024-03-26 Nitya Mani , Edward Yu

In this paper, we study binary constrained codes that are resilient to bit-flip errors and erasures. In our first approach, we compute the sizes of constrained subcodes of linear codes. Since there exist well-known linear codes that achieve…

Information Theory · Computer Science 2023-04-20 V. Arvind Rameshwar , Navin Kashyap

In the early 1980s, Erd\H{o}s and S\'os initiated the study of the classical Tur\'an problem with a uniformity condition: the uniform Tur\'an density of a hypergraph $H$ is the infimum over all $d$ for which any sufficiently large…

Combinatorics · Mathematics 2022-01-21 Matija Bucić , Jacob W. Cooper , Daniel Kráľ , Samuel Mohr , David Munhá Correia

Previous work has shown that the classification of indecomposable off-shell representations of N-supersymmetry, depicted as Adinkras, may be factored into specifying the topologies available to Adinkras, and then the height-assignments for…

High Energy Physics - Theory · Physics 2008-06-17 C. F. Doran , M. G. Faux , S. J. Gates , T. Hubsch , K. M. Iga , G. D. Landweber

Generalized Tur\'an problems have been a central topic of study in extremal combinatorics throughout the last few decades. One such problem is maximizing the number of cliques of size $t$ in a graph of a fixed order that does not contain…

Combinatorics · Mathematics 2024-03-01 Debsoumya Chakraborti , Da Qi Chen

Denote by $\mathcal{C}^-_{\ell}$ the $3$-uniform hypergraph obtained by removing one hyperedge from the tight cycle on $\ell$ vertices. It is conjectured that the Tur\'an density of $\mathcal{C}^-_{5}$ is $1/4$. In this paper, we make…

Combinatorics · Mathematics 2024-03-05 József Balogh , Haoran Luo

The $r$-expansion $G^+$ of a graph $G$ is the $r$-uniform hypergraph obtained from $G$ by enlarging each edge of $G$ with a vertex subset of size $r-2$ disjoint from $V(G)$ such that distinct edges are enlarged by disjoint subsets. Let…

Combinatorics · Mathematics 2015-06-01 Dhruv Mubayi , Jacques Verstraete

We prove that the density of any covering single-insertion code $C\subseteq X^r$ over the $n$-symbol alphabet $X$ cannot be smaller than $1/r+\delta_r$ for some positive real $\delta_r$ not depending on $n$. This improves the volume lower…

Combinatorics · Mathematics 2025-05-27 Oleg Pikhurko , Oleg Verbitsky , Maksim Zhukovskii

This paper is motivated by the question of how global and dense restriction sets in results from extremal combinatorics can be replaced by less global and sparser ones. The result we consider here as an example is Turan's theorem, which…

Combinatorics · Mathematics 2017-07-31 Peter Allen , Julia Böttcher , Jan Hladký , Diana Piguet

Determining the Tur\'an densities of hypergraphs is a notoriously difficult problem at the core of combinatorics. Although Tur\'an posed this problem in 1941, $\pi(K_{\ell}^{(k)})$ remains unknown for all $\ell>k\geq 3$. Prior to this work,…

Combinatorics · Mathematics 2025-02-11 Hong Liu , Bjarne Schülke , Shuaichao Wang , Haotian Yang , Yixiao Zhang

The $n$-dimensional hypercube $Q_n$ is a graph with vertex set $\{0,1\}^n$ such that there is an edge between two vertices if and only if they differ in exactly one coordinate. For any graph $H$, define $\text{ex}(Q_n,H)$ to be the maximum…

Combinatorics · Mathematics 2025-01-08 Alexandr Grebennikov , João Pedro Marciano

Given a $k$-graph $H$ a complete blow-up of $H$ is a $k$-graph $\hat{H}$ formed by replacing each $v\in V(H)$ by a non-empty vertex class $A_v$ and then inserting all edges between any $k$ vertex classes corresponding to an edge of $H$.…

Combinatorics · Mathematics 2021-11-19 Adam Sanitt , John Talbot

We describe odd-length-cube tilings of the n-dimensional q-ary torus what includes q-periodic integer lattice tilings of R^n. In the language of coding theory these tilings correspond to perfect codes with respect to the maximum metric. A…

Combinatorics · Mathematics 2016-01-15 Claudio Qureshi , Sueli I. R. Costa

The Tur\'an hypergraph problem asks to find the maximum number of $r$-edges in a $r$-uniform hypergraph on $n$ vertices that does not contain a clique of size $a$. When $r=2$, i.e., for graphs, the answer is well-known and can be found in…

Combinatorics · Mathematics 2016-10-14 Annie Raymond

Tur\'an problems, which concern the minimum density threshold required for the existence of a particular substructure, are among the most fundamental problems in extremal combinatorics. We study Tur\'an problems for hypergraphs with an…

Combinatorics · Mathematics 2024-08-20 Ander Lamaison

Though embedding problems have been considered for several regular graphs, it is still an open problem for hypercube into torus. In the paper, we prove the conjecture mathematically and obtain the minimum wirelength of embedding for…

Combinatorics · Mathematics 2023-02-28 Zhiyi Tang

We suggest a new approach to obtain bounds on locally correctable and some locally testable binary linear codes, by arguing that these codes (or their subcodes) have coset leader graphs with high discrete Ricci curvature. The bounds we…

Combinatorics · Mathematics 2018-02-08 Eran Iceland , Alex Samorodnitsky

Motivated by modern network communication applications which require low latency, we study codes that correct erasures with low decoding delay. We provide a simple explicit construction that yields convolutional codes that can correct both…

Information Theory · Computer Science 2023-02-20 Serge Kas Hanna , Zhiyuan Tan , Wen Xu , Antonia Wachter-Zeh

The problem of recovering from qubit erasures has recently gained attention as erasures occur in many physical systems such as photonic systems, trapped ions, superconducting qubits and circuit quantum electrodynamics. While several…