{ "id": "1908.01108", "version": "v1", "published": "2019-08-03T02:27:31.000Z", "updated": "2019-08-03T02:27:31.000Z", "title": "Improved bounds for induced poset saturation", "authors": [ "Ryan R. Martin", "Heather C. Smith", "Shanise Walker" ], "categories": [ "math.CO" ], "abstract": "Given a finite poset $\\mathcal{P}$, a family $\\mathcal{F}$ of elements in the Boolean lattice is induced-$\\mathcal{P}$-saturated if $\\mathcal{F}$ contains no copy of $\\mathcal{P}$ as an induced subposet but every proper superset of $\\mathcal{F}$ contains a copy of $\\mathcal{P}$ as an induced subposet. The minimum size of an induced-$\\mathcal{P}$-saturated family in the $n$-dimensional Boolean lattice, denoted $\\operatorname{sat}^*(n,\\mathcal{P})$, was first studied by Ferrara et al. (2017). Our work focuses on strengthening lower bounds. For the 4-point poset known as the diamond, we prove $\\operatorname{sat}^*(n,\\mathcal{D}_2)\\geq\\sqrt{n}$, improving upon a logarithmic lower bound. For the antichain with $k+1$ elements, we prove $\\operatorname{sat}^*(n,\\mathcal{A}_{k+1})\\geq (1-o_k(1))\\frac{kn}{\\log_2 k}$, improving upon a lower bound of $3n-1$ for $k\\geq 3$.", "revisions": [ { "version": "v1", "updated": "2019-08-03T02:27:31.000Z" } ], "analyses": { "subjects": [ "06A07", "05D05" ], "keywords": [ "induced poset saturation", "induced subposet", "dimensional boolean lattice", "logarithmic lower bound", "proper superset" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }