{ "id": "2407.00714", "version": "v1", "published": "2024-06-30T14:34:33.000Z", "updated": "2024-06-30T14:34:33.000Z", "title": "On $Q$-Polynomial distance-regular graphs with a linear dependency involving a $3$-clique", "authors": [ "Mojtaba Jazaeri" ], "comment": "12 pages", "categories": [ "math.CO" ], "abstract": "Let $\\Gamma$ denote a distance-regular graph with diameter $D \\geq 2$. Let $E$ denote a primitive idempotent of $\\Gamma$ with respect to which $\\Gamma$ is $Q$-polynomial. Assume that there exists a $3$-clique $x,y,z$ such that $E\\hat{x},E\\hat{y},E\\hat{z}$ are linearly dependent. In this paper, we classify all the $Q$-polynomial distance-regular graphs $\\Gamma$ with the above property. We describe these graphs from multiple points of view.", "revisions": [ { "version": "v1", "updated": "2024-06-30T14:34:33.000Z" } ], "analyses": { "keywords": [ "polynomial distance-regular graphs", "linear dependency", "multiple points", "linearly dependent", "primitive idempotent" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable" } } }