English

On quasi-orthogonal cocycles

Combinatorics 2019-08-27 v2

Abstract

We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for square {±1}\{\pm 1\}-matrices of size congruent to 22 modulo 44. Quasi-orthogonal cocycles are analogous to the orthogonal cocycles of algebraic design theory. Equivalences with new and known combinatorial objects afforded by this analogy, such as quasi-Hadamard groups, relative quasi-difference sets, and certain partially balanced incomplete block designs, are proved.

Keywords

Cite

@article{arxiv.1902.08808,
  title  = {On quasi-orthogonal cocycles},
  author = {J. A. Armario and D. L. Flannery},
  journal= {arXiv preprint arXiv:1902.08808},
  year   = {2019}
}
R2 v1 2026-06-23T07:48:54.880Z