{ "id": "2101.06877", "version": "v1", "published": "2021-01-18T05:06:08.000Z", "updated": "2021-01-18T05:06:08.000Z", "title": "Spectra of strongly Deza graphs", "authors": [ "Saieed Akbari", "Willem H. Haemers", "Mohammad Ali Hosseinzadeh", "Vladislav V. Kabanov", "Elena V. Konstantinova", "Leonid Shalaginov" ], "categories": [ "math.CO" ], "abstract": "A Deza graph $G$ with parameters $(n,k,b,a)$ is a $k$-regular graph with $n$ vertices such that any two distinct vertices have $b$ or $a$ common neighbours. The children $G_A$ and $G_B$ of a Deza graph $G$ are defined on the vertex set of $G$ such that every two distinct vertices are adjacent in $G_A$ or $G_B$ if and only if they have $a$ or $b$ common neighbours, respectively. A strongly Deza graph is a Deza graph with strongly regular children. In this paper we give a spectral characterisation of strongly Deza graphs, show relationships between eigenvalues, and study strongly Deza graphs which are distance-regular.", "revisions": [ { "version": "v1", "updated": "2021-01-18T05:06:08.000Z" } ], "analyses": { "keywords": [ "distinct vertices", "common neighbours", "study strongly deza graphs", "vertex set", "regular graph" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }