论文标题
在$ {\ rm at4}(p,p,p+2,r)$ - 图形的自动形态组的质谱上
On the prime spectrum of an automorphism group of an ${\rm AT4}(p,p+2,r)$-graph
论文作者
论文摘要
本文致力于$ {\ rm at4}的分类问题(p,p,p+2,r)$ - 图。有一个唯一的$ {\ rm at4}(p,p+2,r)$ - $ p = 2 $,即带有距离传播的soicher图,带有相交阵列$ \ {56、45、16、1; 1、8、8、45、45、56 \} $,其本地图是Isomorphic to Gewirtz的图形。是否存在$ {\ rm at4}(p,p,p+2,r)$ - $ p> 2 $的图仍然不知道。每个$ {\ rm at4}的本地图(p,p+2,r)$ - 图非常规定,带有参数$((p+2)(p^2+4p+2),p(p+3),p-2,p)$。在本文中,我们找到了具有此类参数的强大图形的自动形态组的质谱的上限,并且我们还获得了质量频谱的一些限制,以及$ {\ rm at4}的自动形态组的结构(p,p,p,p,p+2,r)$ p Prime P $是Prime Police prime Power的限制。作为推论,我们表明没有弧传递$ {\ rm at4}(p,p,p+2,r)$ - 带有$ p \ in \ in \ {11,17,27 \} $的图形。
This paper is devoted to the problem of classification of ${\rm AT4}(p,p+2,r)$-graphs. There is a unique ${\rm AT4}(p,p+2,r)$-graph with $p=2$, namely, the distance-transitive Soicher graph with intersection array $\{56, 45, 16, 1;1, 8, 45, 56\}$, whose local graphs are isomorphic to the Gewirtz graph. It is still unknown whether an ${\rm AT4}(p,p+2,r)$-graph with $p>2$ exists. The local graphs of each ${\rm AT4}(p,p+2,r)$-graph are strongly regular with parameters $((p+2)(p^2+4p+2),p(p+3),p-2,p)$. In the present paper, we find an upper bound for the prime spectrum of an automorphism group of a strongly regular graph with such parameters, and we also obtain some restrictions for the prime spectrum and the structure of an automorphism group of an ${\rm AT4}(p,p+2,r)$-graph in case when $p$ is a prime power. As a corollary, we show that there are no arc-transitive ${\rm AT4}(p,p+2,r)$-graphs with $p\in \{11,17,27\}$.