English
Related papers

Related papers: Blocking sets in chain geometries

200 papers

Blocking semiovals and the determination of their (minimum) sizes constitute one of the central research topics in finite projective geometry. In this article we introduce the concept of blocking set with the $r_\infty$-property in a finite…

Combinatorics · Mathematics 2025-07-31 Marilena Crupi , Antonino Ficarra

In this paper, we first study in detail the relationship between minimal linear codes and cutting blocking sets, which were recently introduced by Bonini and Borello, and then completely characterize minimal linear codes as cutting blocking…

Information Theory · Computer Science 2020-04-28 Chunming Tang , Yan Qiu , Qunying Liao , Zhengchun Zhou

We consider the problem of finding the minimal number of points required to intersect all lines in an affine space over the finite field of order 3. We also consider the problem of finding the minimal number of points required to intersect…

Combinatorics · Mathematics 2007-05-23 Ara Aleksanyan , Mihran Papikian

We provide a characterization of graphs of linear rankwidth at most 1 by minimal excluded vertex-minors.

Discrete Mathematics · Computer Science 2011-06-14 Isolde Adler , Arthur M. Farley , Andrzej Proskurowski

Let PG$(r, q)$ be the $r$-dimensional projective space over the finite field ${\rm GF}(q)$. A set $\cal X$ of points of PG$(r, q)$ is a cutting blocking set if for each hyperplane $\Pi$ of PG$(r, q)$ the set $\Pi \cap \cal X$ spans $\Pi$.…

Combinatorics · Mathematics 2020-11-24 Daniele Bartoli , Antonio Cossidente , Giuseppe Marino , Francesco Pavese

Let $n$ be a positive integer. Denote by $\mathrm{PG}(n,q)$ the $n$-dimensional projective space over the finite field $\mathbb{F}_q$ of order $q$. A blocking set in $\mathrm{PG}(n,q)$ is a set of points that has non-empty intersection with…

Group Theory · Mathematics 2009-01-14 Alireza Abdollahi

An $\mathbb{F}_q$-linear set of rank $k$ on a projective line $\mathrm{PG}(1,q^h)$, containing at least one point of weight one, has size at least $q^{k-1}+1$ (see [J. De Beule and G. Van De Voorde, The minimum size of a linear set, J.…

Combinatorics · Mathematics 2020-09-29 Dibyayoti Jena , Geertrui Van de Voorde

In this paper, we show that a small minimal blocking set with exponent e in PG(n,p^t), p prime, spanning a (t/e-1)-dimensional space, is an F_p^e-linear set, provided that p>5(t/e)-11. As a corollary, we get that all small minimal blocking…

Combinatorics · Mathematics 2012-10-04 Peter Sziklai , Geertrui Van de Voorde

Let G be a complete convex geometric graph on 2m vertices, and let F be a family of subgraphs of G. A blocker for F is a set of edges, of smallest possible size, that meets every element of F. In [C. Keller and M. A. Perles, On the smallest…

Combinatorics · Mathematics 2016-07-06 Chaya Keller , Micha A. Perles

We discuss a possible characterization, by means of forbidden configurations, of posets which are embeddable in a product of finitely many scattered chains.

Combinatorics · Mathematics 2008-12-09 Maurice Pouzet , Hamza Si Kaddour , Nejib Zaguia

A small minimal k-blocking set B in PG(n, q), q = pt, p prime, is a set of less than 3(qk + 1)/2 points in PG(n, q), such that every (n - k)-dimensional space contains at least one point of B and such that no proper subset of B satisfies…

Combinatorics · Mathematics 2012-01-17 Geertrui Van de Voorde

Partial spread is important in finite geometry and can be used to construct linear codes. From the results in (Designs, Codes and Cryptography 90:1-15, 2022) by Xia Li, Qin Yue and Deng Tang, we know that if the number of the elements in a…

Information Theory · Computer Science 2023-05-10 W. Lu , X. Wu , X. W. Cao , G. J. Luo , X. P. Qin

The design of block codes for short information blocks (e.g., a thousand or less information bits) is an open research problem which is gaining relevance thanks to emerging applications in wireless communication networks. In this work, we…

Information Theory · Computer Science 2016-10-05 Gianluigi Liva , Lorenzo Gaudio , Tudor Ninacs , Thomas Jerkovits

It is well know that the theory of minimal blocking sets is studied by several author. Another theory which is also studied by a large number of researchers is the theory of hyperplane arrangements. We can remark that the affine space…

Information Theory · Computer Science 2008-02-15 Simona Settepanella

In this paper we prove that a set of points $B$ of PG(n,2) is a minimal blocking set if and only if $<B>=PG(d,2)$ with $d$ odd and $B$ is a set of $d+2$ points of $PG(d,2)$ no $d+1$ of them in the same hyperplane. As a corollary to the…

Group Theory · Mathematics 2007-08-20 Alireza Abdollahi , M. J. Ataei , A. Mohammadi Hassanabadi

The minimum dominating set problem asks for a dominating set with minimum size. First, we determine some vertices contained in the minimum dominating set of a graph. By applying a particular scheme, we ensure that the resulting graph is…

Combinatorics · Mathematics 2025-12-15 Misa Nakanishi

In this paper we provide a generalization of the MPS construction of blocking sets of $PG(r,q^n)$ using subspaces of dimension $s\leq n-2$. By this construction, we determine a new non-planar example in $PG(3,q^6)$.

Combinatorics · Mathematics 2014-05-08 Simone Costa

In the paper, the authors present several new relations and applications for the combinatorial sequence that counts the possible partitions of a finite set with the restriction that the size of each block is contained in a given set. One of…

Combinatorics · Mathematics 2018-04-12 Beáta Bényi , José L. Ramírez

We determine the groups of minimal order in which all groups of order n can embedded for 1 < n < 16. We further determine the order of a minimal group in which all groups or order n or less can be embedded, also for 1 < n < 16.

Group Theory · Mathematics 2017-06-29 Robert Heffernan , Des MacHale , Brendan McCann

In this paper, we study the cardinality of the smallest set of lines of the finite projective spaces $\operatorname{PG}(n,q)$ such that every plane is incident with at least one line of the set. This is the first main open problem…

Combinatorics · Mathematics 2025-04-08 Benedek Kovács , Zoltán Lóránt Nagy , Dávid R. Szabó