5 papers
Butson full propelinear codes
José Andrés Armario, Ivan Bailera, Ronan Egan
In this paper we study Butson Hadamard matrices, and codes over finite rings coming from these matrices in logarithmic form, called BH-codes. We introduce a new morphism of Butson…
Almost supplementary difference sets and quaternary sequences
J. A. Armario, D. L. Flannery
We introduce almost supplementary difference sets (ASDS). For odd , certain ASDS in that have amicable incidence matrices are equivalent to quaternary sequences…
Generalized Hadamard full propelinear codes
José Andrés Armario, Ivan Bailera, Ronan Egan
Codes from generalized Hadamard matrices have already been introduced. Here we deal with these codes when the generalized Hadamard matrices are cocyclic. As a consequence, a new cl…
Generalized binary arrays from quasi-orthogonal cocycles
J. A. Armario, D. L. Flannery
Generalized perfect binary arrays (GPBAs) were used by Jedwab to construct perfect binary arrays. A non-trivial GPBA can exist only if its energy is or a multiple of . This…
On quasi-orthogonal cocycles
J. A. Armario, D. L. Flannery
We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for square -matrices of size congruent to modulo $4…