English

Sum-free cyclic multi-bases and constructions of Ramsey algebras

Combinatorics 2014-12-25 v4

Abstract

Given XZNX\subseteq \mathbb{Z}_N, XX is called a \emph{cyclic basis} if (X+X)X=ZN(X+X)\cup X=\mathbb{Z}_N, \emph{symmetric} if xXx\in X implies xX-x \in X, and \emph{sum-free} if (X+X)X=(X+X)\cap X=\varnothing. We ask, for which mm, NZ+N\in\mathbb{Z}^+ can the set of non-identity elements of ZN\mathbb{Z}_N be partitioned into mm symmetric sum-free cyclic bases? If, in addition, we require that distinct cyclic bases interact in a certain way, we get a proper relation algebra called a Ramsey algebra. Ramsey algebras (which have also been called Monk algebras) have been constructed previously for 2m72\leq m\leq 7. In this manuscript, we provide constructions of Ramsey algebras for every positive integer mm with 2m4002\leq m\leq 400, with the exception of m=8m=8 and m=13m=13.

Keywords

Cite

@article{arxiv.1307.0889,
  title  = {Sum-free cyclic multi-bases and constructions of Ramsey algebras},
  author = {Jeremy F. Alm and Jacob Manske},
  journal= {arXiv preprint arXiv:1307.0889},
  year   = {2014}
}

Comments

14 pages, 2 figures