One of the fastest known general techniques for computing permanents is Ryser’s formula. On this note, we show that this ...

About twenty-five years ago, Horadam and de Launey introduced the cocyclic development of designs, from which the notion ...

This paper deals with partial binary Hadamard matrices. Although there is a fast simple way to generate about a half (which ...

Generalized perfect binary arrays (GPBAs) were used by Jedwab to construct perfect binary arrays. A non-trivial GPBA can ...

In this paper, we give a characterization of quasi-Hadamard groups in terms of propelinear codes. We define a new class ...

A way of generating cocyclic Hadamard matrices is described, which combines a new heuristic, coming from a novel notion ...

A genetic algorithm based robust blind digital watermarking scheme is presented. The experimental results show that our ...

Hadamard ideals were introduced in 2006 as a set of nonlin-ear polynomial equations whose zeros are uniquely related ...

A procedure is described looking for partial Hadamard matrices, as cliques of a particular subgraph Gt of Ito’s Hadamard ...

Progressing on a survey of the state of the art of cocyclic constructions for Hadamard matrices, we will prove that the ...

We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for ...

Provided that a cohomological model for G is known, we describe a method for constructing a basis for n-cocycles over G, ...

An n by n skew-symmetric type (−1, 1)-matrix K = [ki,j ] has 1’s on the main diagonal and ±1’s elsewhere with ki,j = −kj,i. ...

Previously, self-dual codes have been constructed from weighing matrices, and in particular from conference matrices (skew ...

Let G be a semidirect product of finitely generated Abelian groups. We provide a method for constructing an explicit ...

A method for embedding cocyclic submatrices with “large” determinants of orders 2t in certain cocyclic Hadamard matrices ...

Software Project Estimation is one of the most critical and complex task for a Project manager. Several techniques, tools ...

Three algorithms looking for pretty large partial Hadamard ma- trices are described. Here “large” means that hopefully ...

Given two Hadamard matrices of the same order, it can be quite difficult to decide whether or not they are equivalent. ...

An Ant Colony System (ACS) looking for cocyclic Hadamard matrices over dihedral groups D4t is described. The underlying ...

An alternate method for constructing (Hadamard) cocyclic matrices over a finite group GG is described. Provided that a ...

A new reduction on the size of the search space for cocyclic Hadamard matrices over dihedral groups D4t is described, in ...

Levenshtein described in [5] a method for constructing error correcting codes which meet the Plotkin bounds, provided ...

A genetic algorithm for finding cocyclic Hadamard matrices is described. Though we focus on the case of dihedral groups, ...

Let Λ be a commutative ring, A an augmented differential graded algebra over Λ (briefly, DGA-algebra) and X be a relatively ...

Let G be a group which admits the structure of an iterated product of central extensions and semidirect products of abelian ...

We describe a notebook in Mathematica which, taking as input data a homological model for a finite group G of order |G| = ...

An algorithm for calculating a set ofgenerators ofrepresentative 2-cocycles on semidirect product offinite abelian groups ...

We use homological perturbation machinery specific for the algebra category [13] to give an algorithm for computing the ...

Como es bien conocido, los principales mecanismos algebraicos para obtener información homológica de los espacios fibrados ...