{ "id": "2011.09546", "version": "v1", "published": "2020-11-18T21:02:18.000Z", "updated": "2020-11-18T21:02:18.000Z", "title": "Combinatorial proof of the log-convexity for the derangements in the Coxeter groups", "authors": [ "Hiranya Kishore Dey", "Subhajit Ghosh" ], "comment": "21 pages", "categories": [ "math.CO" ], "abstract": "We provide the combinatorial proofs of the log-convexity for the derangement numbers in the symmetric group $\\mathfrak{S}_n$, hyperoctahedral group $\\mathfrak{B}_n$, and the demihyperoctahedral group $\\mathfrak{D}_n$. We also show that the sequences of the even and odd derangement numbers in $\\mathfrak{S}_n$ and $\\mathfrak{B}_n$ are log-convex.", "revisions": [ { "version": "v1", "updated": "2020-11-18T21:02:18.000Z" } ], "analyses": { "subjects": [ "05A20", "05A05" ], "keywords": [ "combinatorial proof", "coxeter groups", "log-convexity", "odd derangement numbers", "symmetric group" ], "note": { "typesetting": "TeX", "pages": 21, "language": "en", "license": "arXiv", "status": "editable" } } }