{ "id": "0912.0720", "version": "v1", "published": "2009-12-03T19:52:37.000Z", "updated": "2009-12-03T19:52:37.000Z", "title": "Independence Complexes of Stable Kneser Graphs", "authors": [ "Benjamin Braun" ], "comment": "submitted", "categories": [ "math.CO", "math.AT" ], "abstract": "For integers n\\geq 1, k\\geq 0, the stable Kneser graph SG_{n,k} (also called the Schrijver graph) has as vertex set the stable n-subsets of [2n+k] and as edges disjoint pairs of n-subsets, where a stable n-subset is one that does not contain any 2-subset of the form {i,i+1} or {1,2n+k}. The stable Kneser graphs have been an interesting object of study since the late 1970's when A. Schrijver determined that they are a vertex critical class of graphs with chromatic number k+2. This article contains a study of the independence complexes of SG_{n,k} for small values of n and k. Our contributions are two-fold: first, we find that the homotopy type of the independence complex of SG_{2,k} is a wedge of spheres of dimension two. Second, we determine the homotopy types of the independence complexes of certain graphs related to SG_{n,2}.", "revisions": [ { "version": "v1", "updated": "2009-12-03T19:52:37.000Z" } ], "analyses": { "subjects": [ "05C69", "57M15" ], "keywords": [ "stable kneser graph", "independence complexes", "homotopy type", "edges disjoint pairs", "stable n-subset" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0912.0720B" } } }