{ "id": "2211.14909", "version": "v1", "published": "2022-11-27T18:16:40.000Z", "updated": "2022-11-27T18:16:40.000Z", "title": "An asymptotic lower bound on the number of polyominoes", "authors": [ "Vuong Bui" ], "comment": "15 pages, 4 figures", "categories": [ "math.CO" ], "abstract": "Let $P(n)$ denote the number of polyominoes of $n$ cells, we show that there exist some positive numbers $A,T$ so that for every $n$, \\[ P(n) \\ge An^{-T\\log n} \\lambda^n, \\] where $\\lambda$ is Klarner's constant, that is $\\lambda=\\lim_{n\\to\\infty} \\sqrt[n]{P(n)}$. This is somewhat a step toward the well known conjecture that there exist positive $A,T$ so that $P(n)\\sim An^{-T}\\lambda^n$ for every $n$. Beside the above theoretical result, we also conjecture that the ratio of the number of inconstructible polyominoes over $P(n)$ is decreasing, by observing this behavior for the available values. The conjecture opens a nice approach to bounding $\\lambda$, since if it is the case, we can conclude that \\[ \\lambda < 4.1141, \\] which is quite close to the currently best lower bound $\\lambda > 4.0025$ and largely improves the currently best upper bound $\\lambda < 4.5252$. The approach is merely analytically manipulating the known or likely properties of the function $P(n)$, instead of giving new insights of the structure of polyominoes.", "revisions": [ { "version": "v1", "updated": "2022-11-27T18:16:40.000Z" } ], "analyses": { "keywords": [ "asymptotic lower bound", "polyominoes", "currently best upper bound", "currently best lower bound", "conjecture opens" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable" } } }