English

An improved bound on the diamond-free poset problem

Combinatorics 2015-03-13 v2

Abstract

In the theory of partially-ordered sets, the two-dimensional Boolean lattice is known as the diamond. In this paper, we show that, if F\mathcal{F} is a family in the nn-dimensional Boolean lattice that has no diamond as a subposet, then F2.206653(nn/2)|\mathcal{F}|\leq 2.206653{n\choose \lfloor n/2\rfloor}, improving a bound by the authors and Michael Young.

Cite

@article{arxiv.1503.00631,
  title  = {An improved bound on the diamond-free poset problem},
  author = {Lucas Kramer and Ryan R. Martin},
  journal= {arXiv preprint arXiv:1503.00631},
  year   = {2015}
}

Comments

The paper has been withdrawn. There is an irreparable error in Lemma 9

R2 v1 2026-06-22T08:42:10.335Z