23 papers
-numbers of covers in characteristic two: semigroups and Riemann-Roch spaces
Gilberto B. Almeida Filho, Saeed Tafazolian, Stéfani C. Vieira
We compute the -numbers of the Garcia-Güneri-Stichtenoth curves, the Beelen-Montanucci curves, and the Skabelund covers of Suzuki curves in characteristic two. The proofs use th…
-Numbers, higher Cartier ranks and maximality of van der Geer-van der Vlugt curves
Gilberto B. Almeida Filho, Saeed Tafazolian, Stéfani C. Vieira
Let be an odd prime and let be the van der Geer-van der Vlugt curve over an algebraically closed field of characteristic , where $R(x)=\sum_{i=0}^{h}a_ix…
A Quadratic Bound for Automorphism Groups of Curves of Positive -Rank in Odd Characteristic
Saeed Tafazolian
Let be a nonsingular projective curve of genus over an algebraically closed field of odd characteristic . Giulietti and Korchmáros established a quadratic genus boun…
Sharp bounds and gap phenomena for large -subgroups of automorphism groups of curves
Saeed Tafazolian
Let be a curve of genus over an algebraically closed field of odd characteristic , and let . A theorem of Giulietti and Korchmaros shows that if $…
Cyclic automorphisms beyond the canonical bound
Ahmad Kazemifard, Saeed Tafazolian
Let X be a smooth projective curve of genus g >= 2 over an algebraically closed field K, and suppose that Aut(X) contains a cyclic subgroup G of order N > 2g - 2. The cases N >= 2g…
Nonexistence of maximal curves of genus five over $\F_{64}$
Gilberto B. Almeida Filho, Saeed Tafazolian, Stéfani C. Vieira
We show that there is no maximal curve of genus five over $\F_{64}$. As a consequence, , and the genus spectrum of maximal curves over $\F_{64}$ is determined. The p…
On the generalized Ree curve
Ahmad Kazemifard, Saeed Tafazolian
Let p be an odd prime, let q_0 := p^s with s >= 1, and put q := p q_0^2. We study the smooth projective curve R_{p,s} with function field F_q(x,y,z), y^q - y = x^{q_0}(x^q - x), z^…
A classification of zero -rank curves with large automorphism groups in odd characteristic
Saeed Tafazolian
Let $\cX$ be a curve of genus and -rank zero over an algebraically closed field of odd characteristic , and let $G\le\Aut(\cX)$ satisfy . We prove that…
A characterization of the Ree curve
Saeed Tafazolian
Let , where and . We prove that a smooth, projective, geometrically irreducible curve over $\F_q$ with rational points and genus \[ \frac32q_0(q-…
Transitive automorphism groups of maximal curves
Saeed Tafazolian
Let be an odd prime power and let be a maximal curve of genus at least two over $\F_{q^2}$. We prove that the automorphism group of acts transitively on its rational po…
Nakajima-extremal Artin--Schreier covers of ordinary elliptic curves in characteristic
Saeed Tafazolian
Let be an algebraically closed field of characteristic and let , . We construct ordinary bielliptic curves of genus for which \[ \Aut(X)\cong \Dih(C…
On Skabelund's Ray Class Field Covers of the Suzuki and Ree Curves
Saeed Tafazolian
Let $\Sm_q$ and $\Rm_q$ denote the Suzuki and Ree curves. Motivated by the Giulietti--Korchmáros curve, Skabelund constructed cyclic covers $\tSm_q$ and $\tRm_q$ of these curves an…
Explicit LCP of MDS Codes and LCD Codes on Hyperelliptic Curves via Mumford Representation
Adler Marques, Yuri da Silva, Saeed Tafazolian
We study algebraic geometry codes on hyperelliptic curves of genus equipped with a rational Weierstrass point, with a focus on complementarity properties. Our first cont…
Jacobian algebras and variation of hyperplane sections
Giovanna Ilardi, Abbas Nasrollah Nejad, Saeed Tafazolian
We study the variation in moduli of hyperplane sections of a hypersurface with at most isolated singularities. Using the Milnor algebra , we give…
On the Maximality, Weierstrass Semigroups, and Automorphism Group of the Curve
João Paulo Guardieiro, Yuri da Silva, Saeed Tafazolian
We study the algebraic curve over defined by , where is a positive integer coprime to the characteristic. We first prove (when is o…
Construction of Non-special Divisors on Kummer Covers With Arbritary Ramification For LCP Codes
Adler Marques, Yuri da Silva, Saeed Tafazolian
Linear Complementary Pairs (LCP) of algebraic geometry (AG) codes offer strong resistance against side-channel and fault-injection attacks, but their construction depends criticall…
Veronese Avoiding Hypersurfaces
Giovanna Ilardi, Abbas Nasrollah Nejad, Saeed Tafazolian
We introduce Veronese-Avoiding hypersurfaces, inspired by the theory of associated forms of Alper--Isaev. In the smooth case, we reinterpret their criterion via Macaulay inverse sy…
Maximal Subcovers of the Skabelund Curve: Uniqueness via Genus and Automorphism Groups
Gilberto B. Almeida Filho, Saeed Tafazolian, Stéfani C. Vieira
We establish a rigidity phenomenon for a family of intermediate covers of the Skabelund curve over . The Skabelund curve, introduced by D.~Skabelund as a cyclic c…
Hankel edge ideals of trees and (semi-)Hamiltonian graphs
Dariush Kiani, Sara Saeedi Madani, Saeed Tafazolian
In this paper, we study the Hankel edge ideals of graphs. We determine the minimal prime ideals of the Hankel edge ideal of labeled Hamiltonian and semi-Hamiltonian graphs, and we…
The -number of Certain Hyperelliptic Curves
Vahid Nourozi, Farhad Rahmati, Saeed Tafazolian
In this paper, we compute a formula for the -number of certain hyperelliptic curves given by the equation for infinitely many values of . The same question is st…
On certain maximal hyperelliptic curves related to Chebyshev polynomials
Saeed Tafazolian, Jaap Top
We study hyperelliptic curves arising from Chebyshev polynomials. The aim of this paper is to characterize the pairs such that the hyperelliptic curve $\cC$ over a finite f…
On the spectrum for the genera of maximal curves over small fields
Nazar Arakelian, Saeed Tafazolian, Fernando Torres
Motivated by previous computations in Garcia, Stichtenoth and Xing (2000) paper ,we discuss the spectrum for the genera of maximal curves over finite fields of or…
Covered by Lines and Conic Connected Varieties
Simone Marchesi, Alex Massarenti, Saeed Tafazolian
We study some properties of an embedded variety covered by lines and give a numerical criterion ensuring the existence of a singular conic through two of its general points. We sho…