摘要
群G关于其不包含单位元1的子集S的Cayley图Γ∶=Cay(G,S)称为正规的,如果G的右正则表示R(G)在Aut(Γ)中正规;称图Γ是G的正则表示(GRR),如果R(G)=Aut(Γ)且Γ是无向图.该文完全解决了32p阶二面体群G=〈a,b|a16p=b2=1,ab=a-1〉(其中p是奇素数)的连通3度无向Cayley图的正规性问题,并获得了该群的一批3度GRR的例子.
A Cayley graphΓ∶=Cay(G,S)of the group G with its subset S1 is said to be normal if R(G),the group of right multiplications is normal in Aut(Γ);The graphΓis said GRR if R(G)=Aut(Γ)andΓis undirected.In this paper,we solve completely the problem for the normality of3-valent Cayley graphs of dihedral groups with order 32 p,G=〈a,b|a16 p=b2=1,ab=a-1〉,where pis an odd prime.In addition,we obtain many infinite families of 3-valent graphical regular representations for the group G.
引文
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