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Related papers: Saturating linear sets in PG$(2,q^4)$

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Motivated by questions in theoretical computer science and quantum information theory, we study the classical problem of determining linear spaces of matrices of bounded rank. Spaces of bounded rank three were classified in 1983, and it has…

Algebraic Geometry · Mathematics 2023-06-27 Hang Huang , J. M. Landsberg

In this paper we consider two pointsets in $\mathrm{PG}(2,q^n)$ arising from a linear set $L$ of rank $n$ contained in a line of $\mathrm{PG}(2,q^n)$: the first one is a linear blocking set of R\'edei type, the second one extends the…

Combinatorics · Mathematics 2021-12-23 Vito Napolitano , Olga Polverino , Paolo Santonastaso , Ferdinando Zullo

In this paper, we first determine the minimum possible size of an Fq-linear set of rank k in PG(1, q^n). We obtain this result by relating it to the number of directions determined by a linearized polynomial whose domain is restricted to a…

Combinatorics · Mathematics 2018-04-23 Jan De Beule , Geertrui Van de Voorde

For a fixed poset $\mathcal P$ we say that a family $\mathcal F\subseteq\mathcal P([n])$ is $\mathcal P$-saturated if it does not contain an induced copy of $\mathcal P$, but whenever we add a new set to $\mathcal F$, we form an induced…

Combinatorics · Mathematics 2026-03-10 Maria-Romina Ivan , Sean Jaffe

In this paper, we investigate the Andr\'e/Bruck-Bose representation of certain $\mathbb{F}_q$-linear sets contained in a line of $\text{PG}(2,q^t)$. We show that scattered $\mathbb{F}_q$-linear sets of rank $3$ in $\text{PG}(1,q^3)$…

Combinatorics · Mathematics 2023-07-28 Lins Denaux , Jozefien D'haeseleer , Geertrui Van de Voorde

An $\mathbb{F}_q$- linear set $L=L_U$ of $\Lambda=\mathrm{PG}(V, \mathbb{F}_{q^n}) \cong \mathrm{PG}(r-1,q^n)$ is a set of points defined by non-zero vectors of an $\mathbb{F}_q$-subspace $U$ of $V$. The integer $\dim_{\mathbb{F}_q} U$ is…

Combinatorics · Mathematics 2024-05-03 Giovanni Giuseppe Grimaldi , Somi Gupta , Giovanni Longobardi , Rocco Trombetti

We classify nets of conics in Desarguesian projective planes over finite fields of odd order, namely, two-dimensional linear systems of conics containing a repeated line. Our proof is geometric in the sense that we solve the equivalent…

Combinatorics · Mathematics 2020-03-16 Michel Lavrauw , Tomasz Popiel , John Sheekey

An untouchable set in a projective plane is a set of points such that no line of the plane meets the set in exactly one point. Recently, H\'eger and Nagy (Avoiding Secants of Given Size in Finite Projective Planes, J. Combin. Des.…

Combinatorics · Mathematics 2025-05-14 Jeremy M. Dover

The rank of a scattered $\mathbb{F}_q$-linear set of $\mathrm{PG}(r-1,q^n)$, $rn$ even, is at most $rn/2$ as it was proved by Blokhuis and Lavrauw. Existence results and explicit constructions were given for infinitely many values of $r$,…

Combinatorics · Mathematics 2017-01-25 Bence Csajbók , Giuseppe Marino , Olga Polverino , Ferdinando Zullo

If an Fq-linear set LU in a projective space is defined by a vector subspace U which is linear over a proper superfield of Fq, then all of its points have weight at least 2. It is known that the converse of this statement holds for linear…

Combinatorics · Mathematics 2021-09-28 Dibyayoti Jena , Geertrui Van de Voorde

We introduce a family of linear sets of $\mathrm{PG}(1,q^{2n})$ arising from maximum scattered linear sets of pseudoregulus type of $\mathrm{PG}(3,q^{n})$. For $n=3,4$ and for certain values of the parameters we show that these linear sets…

Combinatorics · Mathematics 2017-07-27 Bence Csajbók , Giuseppe Marino , Olga Polverino , Corrado Zanella

A $0$-$1$ matrix $M$ is saturating for a $0$-$1$ matrix $P$ if $M$ does not contain a submatrix that can be turned into $P$ by changing some $1$ entries to $0$ entries, and changing an arbitrary $0$ to $1$ in $M$ introduces such a submatrix…

Combinatorics · Mathematics 2023-10-05 Radoslav Fulek , Balázs Keszegh

Saturation problems for forbidden graphs have been a popular area of research for many decades, and recently Brualdi and Cao initiated the study of a saturation problem for 0-1 matrices. We say that 0-1 matrix $A$ is saturating for the…

Combinatorics · Mathematics 2020-12-29 Jesse Geneson

This paper aims to study linear sets of minimum size in the projective line, that is $\mathbb{F}_q$-linear sets of rank $k$ in $\mathrm{PG}(1,q^n)$ admitting one point of weight one and having size $q^{k-1}+1$. Examples of these linear sets…

Combinatorics · Mathematics 2022-01-07 Vito Napolitano , Olga Polverino , Paolo Santonastaso , Ferdinando Zullo

A class of scattered linearized polynomials covering infinitely many field extensions is exhibited. More precisely, the $q$-polynomial over $\mathbb F_{q^6}$, $q \equiv 1\pmod 4$ described in arXiv:1906.05611, arXiv:1910.02278 is…

Combinatorics · Mathematics 2021-01-26 Giovanni Longobardi , Corrado Zanella

A graph $H^{\prime}$ is $(H, G)$-saturated if it is $G$-free and the addition of any edge of $H$ not in $H^{\prime}$ creates a copy of $G$. The saturation number $sat(H, G)$ is the minimum number of edges in a $(H, G)$-saturated graph. We…

Combinatorics · Mathematics 2014-11-12 Kavish Gandhi , Chiheon Kim

Linearized polynomials appear in many different contexts, such as rank metric codes, cryptography and linear sets, and the main issue regards the characterization of the number of roots from their coefficients. Results of this type have…

Combinatorics · Mathematics 2020-05-07 Olga Polverino , Ferdinando Zullo

The saturation number of a graph $G$ is the cardinality of any smallest maximal matching of $G$, and it is denoted by $s(G)$. Fullerene graphs are cubic planar graphs with exactly twelve 5-faces; all the other faces are hexagons. They are…

Combinatorics · Mathematics 2014-05-12 Vesna Andova , František Kardoš , Riste Škrekovski

Let $F$ be a graph and $\mathcal{H}$ be a hypergraph, both embedded on the same vertex set. We say $\mathcal{H}$ is a Berge-$F$ if there exists a bijection $\phi:E(F)\to E(\mathcal{H})$ such that $e\subseteq \phi(e)$ for all $e\in E(F)$. We…

Combinatorics · Mathematics 2023-12-04 Sean English , Jürgen Kritschgau , Mina Nahvi , Elizabeth Sprangel

We show that the number of linear spaces on a set of $n$ points and the number of rank-3 matroids on a ground set of size $n$ are both of the form $(cn+o(n))^{n^2/6}$, where $c=e^{\sqrt 3/2-3}(1+\sqrt 3)/2$. This is the final piece of the…

Combinatorics · Mathematics 2024-05-31 Matthew Kwan , Ashwin Sah , Mehtaab Sawhney