{ "id": "math/9909050", "version": "v4", "published": "1999-09-09T12:03:27.000Z", "updated": "2001-12-20T16:55:19.000Z", "title": "Vassiliev invariants and rational knots of unknotting number one", "authors": [ "A. Stoimenow" ], "comment": "13 pages, 2 figures; revision 26 Nov 99: added reference [OTY], discussion of signatures, branched cover homology and 4-genera, more problems; revision 7 Sep 01: Theorem 1.2 slightly improved, a few other minor structural changes; revision 20 Dec 01: final version, Theorem 1.2 improved, 2 sections removed", "journal": "Topology 42(1) (2003), 227--241.", "categories": [ "math.GT" ], "abstract": "Introducing a way to modify knots using $n$-trivial rational tangles, we show that knots with given values of Vassiliev invariants of bounded degree can have arbitrary unknotting number (extending a recent result of Ohyama, Taniyama and Yamada). The same result is shown for 4-genera and finite reductions of the homology group of the double branched cover. Closer consideration is given to rational knots, where it is shown that the number of $n$-trivial rational knots of at most $k$ crossings is for any $n$ asymptotically at least $C^{(\\ln k)^2}$ for any $C<\\sqrt[2\\ln 2]{e}$.", "revisions": [ { "version": "v4", "updated": "2001-12-20T16:55:19.000Z" } ], "analyses": { "subjects": [ "57M25" ], "keywords": [ "vassiliev invariants", "trivial rational tangles", "trivial rational knots", "arbitrary unknotting number", "finite reductions" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "1999math......9050S" } } }