Hypergroups over the group and generalizations of Schreier's theorem on group extensions

Samuel H. Dalalyan

Let $H$ be a group, $m$ be a positive integer, $Ex{t}_{m}H$ be the set of all isomorphic in $G$ classes of group monomorphisms $\phi :H\to G$ such that index of $\phi (H)$ in $G$ is…