{ "id": "2402.10025", "version": "v2", "published": "2024-02-15T15:45:44.000Z", "updated": "2024-05-30T14:07:46.000Z", "title": "An improved lower bound on the Shannon capacities of complements of odd cycles", "authors": [ "Daniel G. Zhu" ], "comment": "7 pages, 1 figure", "categories": [ "math.CO", "cs.IT", "math.IT" ], "abstract": "Improving a 2003 result of Bohman and Holzman, we show that for $n \\geq 1$, the Shannon capacity of the complement of the $2n+1$-cycle is at least $(2^{r_n} + 1)^{1/r_n} = 2 + \\Omega(2^{-r_n}/r_n)$, where $r_n = \\exp(O((\\log n)^2))$ is the number of partitions of $2(n-1)$ into powers of $2$. We also discuss a connection between this result and work by Day and Johnson in the context of graph Ramsey numbers.", "revisions": [ { "version": "v2", "updated": "2024-05-30T14:07:46.000Z" } ], "analyses": { "subjects": [ "94A24", "05C38", "05C55" ], "keywords": [ "shannon capacity", "lower bound", "odd cycles", "complement", "graph ramsey numbers" ], "note": { "typesetting": "TeX", "pages": 7, "language": "en", "license": "arXiv", "status": "editable" } } }