2023/08/22 by Mandal, Santanu, Manna, Pallabi
#05C25 #Combinatorics (math.CO) #FOS: Mathematics
paper · doi:10.48550/arxiv.2308.11301
Let G be a group. The intersection subgroup graph of G (introduced by Anderson et al. \citeanderson) is the simple graph ΓS(G) whose vertices are those non-trivial subgroups say H of G with H∩ K=\e\ for some non-trivial subgroup K of G; two distinct vertices H and K are adjacent if and only if H∩ K=\e\, where e is the identity element of G. In this communication, we explore the groups whose intersection subgroup graph belongs to several significant graph classes including cluster graphs, perfect graphs, cographs, chordal graphs, bipartite graphs, triangle-free and claw-fee graphs. We categorize each nilpotent group G so that ΓS(G) belongs to the above classes. We entirely classify the simple group of Lie type whose intersection subgroup graph is a cograph. Moreover, we deduce that ΓS(G) is neither a cograph nor a chordal graph if G is a torsion-free nilpotent group.