Counting -groups and nilpotent groups
Let and be two groups of finite order , and suppose that they share a normal subgroup such that if or . Cases when is cyclic or dihedral and when for exactly pairs have been shown to be of crucial importance when studying pairs of 2-groups with the latter property. In such cases one can describe two general constructions how to get all possible from a given . The constructions, denoted by and , respectively, depend on a coset (or two cosets and ) modulo , and on an...
Let G be a finite group, and (p ≥ 3). It is proved that G ≅ M if G and M have the same order components.
We present a survey of results on word equations in simple groups, as well as their analogues and generalizations, which were obtained over the past decade using various methods: group-theoretic and coming from algebraic and arithmetic geometry, number theory, dynamical systems and computer algebra. Our focus is on interrelations of these machineries which led to numerous spectacular achievements, including solutions of several long-standing problems.
It is a known result that if a finite abelian group of odd order is a direct product of lacunary cyclic subsets, then at least one of the factors must be a subgroup. The paper gives an elementary proof that does not rely on characters.