<p>A rank 3 graph is an orbital graph of a rank 3 permutation group of even order. Despite the completion of the classification of rank 3 graphs (see, e.g., Chapter 11 of the recent monograph Strongly regular graphs by Brouwer and Van&#xa0;Maldeghem), the full automorphism groups of these graphs (equivalently, the 2-closures of rank 3 groups) have not been explicitly described, though a lot of information on this subject is available. In the present note, we address this problem for the affine rank 3 graphs. We find the automorphism groups for finitely many relatively small graphs and show that modulo known results, this provides a complete description of the automorphism groups of the affine rank 3 graphs, thus reducing the general problem to the case when the socle of the automorphism group is nonabelian simple.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

The Automorphism Groups of Small Affine Rank 3 Graphs

  • Jin Guo,
  • Andrey V. Vasil’ev,
  • Rui Wang

摘要

A rank 3 graph is an orbital graph of a rank 3 permutation group of even order. Despite the completion of the classification of rank 3 graphs (see, e.g., Chapter 11 of the recent monograph Strongly regular graphs by Brouwer and Van Maldeghem), the full automorphism groups of these graphs (equivalently, the 2-closures of rank 3 groups) have not been explicitly described, though a lot of information on this subject is available. In the present note, we address this problem for the affine rank 3 graphs. We find the automorphism groups for finitely many relatively small graphs and show that modulo known results, this provides a complete description of the automorphism groups of the affine rank 3 graphs, thus reducing the general problem to the case when the socle of the automorphism group is nonabelian simple.