6533b7dafe1ef96bd126ea01

RESEARCH PRODUCT

Rank formulae for factorized groups

F. De GiovanniF. De GiovanniF. De GiovanniSilvana FranciosiSilvana FranciosiSilvana FranciosiBernhard AmbergBernhard AmbergBernhard Amberg

subject

CombinatoricsPure mathematicsGroup (mathematics)General MathematicsAlgebra over a fieldRank (differential topology)Mathematics

description

The following inequalities for the torsion-free rank r0(G) of the group G=AB and for the p∞-rank rp(G) of the soluble-by-finite group G=AB are stated: $$\begin{gathered} r_0 (G) \leqslant r_0 (A) + r_0 (B) - r_0 (A \cap B), \hfill \\ r_p (G) \leqslant r_p (A) + r_p (B) - r_p (A \cap B). \hfill \\ \end{gathered} $$

https://doi.org/10.1007/bf01058710