Permutability degrees of finite groups

Daniele Ettore Otera, Francesco G. Russo

Given a finite group $G$, we introduce the \textit{permutability degree} of $G$, as $$pd(G)=\frac{1}{|G||\mathcal{L}(G)|}\sum _{X\in \mathcal{L}(G)}|P_G(X)|,$$ where…