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arXiv · 1909.10896

$IP^\star$ set in product space of countable adequate commutative partial semigroups

Abstract

A partial semigroup is a set with restricted binary operation. In this work we will extend a result due to V. Bergelson and N. Hindman concerning the rich structure presented in the product space of semigroups to partial semigroup. An $IP^{\star}$ set in a semigroup is a set that intersect every set of the form $\left\{ FS(x_{n})_{n=1}^{\infty}:x_{n}\in S\right\} $. V. Bergelson and N. Hindman proved that if $S_{1},S_{2},\ldots,S_{l}$ are finite collection of commutative semigroup, then under certain condition, an $IP^{\star}$ set in $S_{1}\times S_{2}\times\ldots\times S_{l}$ contains cartesian products of arbitrarily large finite substructures of the form $FS\left(x_{1,n}\right)_{n=1}^{\infty}\times FS\left(x_{2,n}\right)_{n=1}^{\infty}\times\ldots\times FS\left(x_{l,n}\right)_{n=1}^{\infty}$. In this work we will extend this result to countable adequate commutative partial semigroup.

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BibTeXRIS

Aninda Chakraborty. 2019-09-22. $IP^\star$ set in product space of countable adequate commutative partial semigroups. https://arxiv.org/abs/1909.10896

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