{ "id": "1512.03361", "version": "v1", "published": "2015-12-10T18:33:35.000Z", "updated": "2015-12-10T18:33:35.000Z", "title": "MDS codes in the Doob graphs", "authors": [ "Evgeny Bespalov", "Denis Krotov" ], "comment": "In Russian, 30 pp", "categories": [ "math.CO", "cs.IT", "math.IT" ], "abstract": "The Doob graph $D(m,n)$, where $m>0$, is the direct product of $m$ copies of The Shrikhande graph and $n$ copies of the complete graph $K_4$ on $4$ vertices. The Doob graph $D(m,n)$ is a distance-regular graph with the same parameters as the Hamming graph $H(2m+n,4)$. In this paper we consider MDS codes in Doob graphs with code distance $d \\ge 3$. We prove that if $2m+n>6$ and $2