On Alternating and Symmetric Groups Which Are Quasi OD-Characterizable

Abstract

Let $\Gamma(G)$ be the prime graph associated with a finite group $G$ and $D(G)$ be the degree pattern of $G$. A finite group $G$ is said to be $k$-fold OD-characterizable if there exist exactly $k$ non-isomorphic groups $H$ such that $|H|=|G|$ and $D(H)=D(G)$. The purpose of this article is twofold. First, it shows that the symmetric group $S_{27}$ is $38$-fold OD-charaterizable. Second, it shows that there exist many infinite families of alternating and symmetric groups, $\{A_n\}$ and $\{S_n\}$, which are $k$-fold OD-characterizable with $k>3$.