{ "id": "2102.00443", "version": "v1", "published": "2021-01-31T13:04:54.000Z", "updated": "2021-01-31T13:04:54.000Z", "title": "Pattern occurrences in $k$-ary words revisited: a few new and old observations", "authors": [ "Toufik Mansour", "Reza Rastegar" ], "categories": [ "math.CO" ], "abstract": "In this paper, we study the pattern occurrence in $k$-ary words. We prove an explicit upper bound on the number of $k$-ary words avoiding any given pattern using a random walk argument. Additionally, we reproduce several already known results and establish a simple connection among pattern occurrences in permutations and $k$-ary words. A simple consequence of this connection is that Wilf-equivalence of two patterns in words implies their Wilf-equivalence in permutations.", "revisions": [ { "version": "v1", "updated": "2021-01-31T13:04:54.000Z" } ], "analyses": { "subjects": [ "05A05", "05A16", "05C81" ], "keywords": [ "ary words", "pattern occurrence", "old observations", "random walk argument", "explicit upper bound" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }