Classification of distance-transitive orbital graphs of overgroups of the Jevons group
B. A. Pogorelova,
M. A. Pudovkinab a Academy of Cryptography of Russian Federation
b Bauman Moscow State Technical University
Abstract:
The Jevons group
$A{\tilde S_n}$ is an isometry group of the Hamming metric on the
$n$-dimensional vector space
${V_n}$ over
$GF(2)$. It is generated by the group of all permutation
$(n \times n)$-matrices over
$GF(2)$ and the translation group on
${V_n}$. Earlier the authors of the present paper classified the submetrics of the Hamming metric on
${V_n}$ for
$n \geqslant 4$, and all overgroups of
$A{\tilde S_n}$ which are isometry groups of these overmetrics. In turn, each overgroup of
$A{\tilde S_n}$ is known to define orbital graphs whose “natural” metrics are submetrics of the Hamming metric. The authors also described all distance-transitive orbital graphs of overgroups of the Jevons group
$A{\tilde S_n}$. In the present paper we classify the distance-transitive orbital graphs of overgroups of the Jevons group. In particular, we show that some distance-transitive orbital graphs are isomorphic to the following classes: the complete graph
${K_{{2^n}}}$, the complete bipartite graph
${K_{{2^{n - 1}}{{,2}^{n - 1}}}}$, the halved
$(n + 1)$-cube, the folded
$(n + 1)$-cube, the graphs of alternating forms, the Taylor graph, the Hadamard graph, and incidence graphs of square designs.
Keywords:
orbital graph, the Jevons group, distance-transitive graphs, Hamming graph, Taylor graph, Hadamard graph.
UDC:
519.172+
512.542.7 Received: 28.11.2017
DOI:
10.4213/dm1487