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Minimal codes are linear codes where all non-zero codewords are minimal, i.e., whose support is not properly contained in the support of another codeword. The minimum possible length of such a $k$-dimensional linear code over $\mathbb{F}_q$…

Combinatorics · Mathematics 2025-06-06 Vladimir Chubenko , Sascha Kurz

Subspace codes form the appropriate mathematical setting for investigating the Koetter-Kschischang model of fault-tolerant network coding. The Main Problem of Subspace Coding asks for the determination of a subspace code of maximum size…

Combinatorics · Mathematics 2014-08-07 Haiteng Liu , Thomas Honold

New bounds on the cardinality of permutation codes equipped with the Ulam distance are presented. First, an integer-programming upper bound is derived, which improves on the Singleton-type upper bound in the literature for some lengths.…

Information Theory · Computer Science 2015-04-21 Faruk Göloğlu , Jüri Lember , Ago-Erik Riet , Vitaly Skachek

We introduce \emph{Term Coding}, a novel framework for analysing extremal problems in discrete mathematics by encoding them as finite systems of \emph{term equations} (and, optionally, \emph{non-equality constraints}). In its basic form,…

Combinatorics · Mathematics 2025-10-07 Søren Riis

The sum-rank metric provides a unifying framework that generalizes both the celebrated Hamming and rank metrics, and has found applications in areas such as network coding, distributed storage, and space-time coding. A central problem is to…

Information Theory · Computer Science 2026-05-01 Aida Abiad , Antonina P. Khramova , Sven C. Polak , Ferdinando Zullo

Separable codes were introduced to provide protection against illegal redistribution of copyrighted multimedia material. Let $\mathcal{C}$ be a code of length $n$ over an alphabet of $q$ letters. The descendant code ${\sf…

Information Theory · Computer Science 2015-07-06 Minquan Cheng , Jing Jiang , Haiyan Li , Ying Miao , Xiaohu Tang

We generalize the Griesmer bound in the case of systematic codes over a field of size q greater than the distance d of the code. We also generalize the Griesmer bound in the case of any systematic code of distance 2,3,4 and in the case of…

Information Theory · Computer Science 2013-10-16 Emanuele Bellini

In this paper we introduce and study line Hermitian Grassmann codes as those subcodes of the Grassmann codes associated to the $2$-Grassmannian of a Hermitian polar space defined over a finite field of square order. In particular, we…

Combinatorics · Mathematics 2025-10-20 Ilaria Cardinali , Luca Giuzzi

Given any linear code $C$ over a finite field $GF(q)$ we show how $C$ can be described in a transparent and geometrical way by using the associated Bruen-Silverman code. Then, specializing to the case of MDS codes we use our new approach to…

Combinatorics · Mathematics 2023-01-23 T. L. Alderson , A. A. Bruen , R. Silverman

We study Euclidean designs from the viewpoint of the potential energy. For a finite set in Euclidean space, We formulate a linear programming bound for the potential energy by applying harmonic analysis on a sphere. We also introduce the…

Combinatorics · Mathematics 2012-06-29 Tsuyoshi Miezaki , Makoto Tagami

AG codes correspond geometrically to points in the Grassmannian of k-planes in an n-dimensional projective space PG(n, F_q) defined over a finite field F_q of q elements. We prove that invariant subgrassmannians by the action of a triangle…

Combinatorics · Mathematics 2017-06-20 Alberto Besana , Cristina Martínez-Ramírez

We construct two series of linear codes over finite ring $\mathbb{F}_{q}[x]/(x^2)$ and Galois ring $GR(p^2,m)$ respectively reaching the Griesmer bound. They derive two series of codes over finite field $\mathbb{F}_{q}$ by Gray map. The…

Information Theory · Computer Science 2016-12-06 Jin Li , Aixian Zhang , Keqin Feng

A large family of linear codes with flexible parameters from almost bent functions and perfect nonlinear functions are constructed and their parameters are determined. Some constructed linear codes and their related codes are optimal in the…

Information Theory · Computer Science 2019-03-20 Weiqiong Wang , Yan Wang

We investigate the asymptotic rates of length-$n$ binary codes with VC-dimension at most $dn$ and minimum distance at least $\delta n$. Two upper bounds are obtained, one as a simple corollary of a result by Haussler and the other via a…

Information Theory · Computer Science 2018-08-31 Sihuang Hu , Nir Weinberger , Ofer Shayevitz

We establish upper bounds for the distance to finite-dimensional subspaces in inner product spaces and improve some generalisations of Bessel's inequality obtained by Boas, Bellman and Bombieri. Refinements of the Hadamard inequality for…

Metric Geometry · Mathematics 2009-09-29 Sever Silvestru Dragomir

We examine an error-correcting coding framework in which each coded symbol is constrained to be a function of a fixed subset of the message symbols. With an eye toward distributed storage applications, we seek to design systematic codes…

Information Theory · Computer Science 2015-02-23 Wael Halbawi , Matthew Thill , Babak Hassibi

We initiate study of the Terwilliger algebra and related semidefinite programming techniques for the conjugacy scheme of the symmetric group Sym$(n)$. In particular, we compute orbits of ordered pairs on Sym$(n)$ acted upon by conjugation…

Combinatorics · Mathematics 2013-11-08 Mathieu Bogaerts , Peter Dukes

Codes in finite projective spaces equipped with the subspace distance have been proposed for error control in random linear network coding. The resulting so-called \emph{Main Problem of Subspace Coding} is to determine the maximum size…

Combinatorics · Mathematics 2018-08-30 Thomas Honold , Michael Kiermaier , Sascha Kurz

Studying the generalized Hamming weights of linear codes is a significant research area within coding theory, as it provides valuable structural information about the codes and plays a crucial role in determining their performance in…

Information Theory · Computer Science 2024-05-31 Wei Lu , Qingyao Wang , Xiaoqiang Wang , Dabin Zheng

This paper considers the quantization problem on the Grassmann manifold \mathcal{G}_{n,p}, the set of all p-dimensional planes (through the origin) in the n-dimensional Euclidean space. The chief result is a closed-form formula for the…

Information Theory · Computer Science 2007-07-13 Wei Dai , Youjian Liu , Brian Rider