3 papers
math.CO2019
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…
math.CO2019
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…
math.CO2019
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…