set is called -set in a semigroup if it contains finite products of a sequence. A set that intersects with all -sets is called -set. It is a well known and established result by Bergelson and Hindman that if is an -set, then for any sequence , there exists a sum subsystem such that . In \cite[Question 3]{G}, S. Goswami posed the question: if we replace the single sequence by -sequences, then is it possible to obtain a sum subsystem such that all of its zigzag finite sums and products will be in . Goswami has given affirmative answers only for dynamical -sets which are not equivalent to those of -sets, but are rather significantly stronger. In this article, we will give the answer to Goswami’s question that was unknown until now.

生成讲解博客的中文版本

生成AI智能校验的中文版本