TY - JOUR
ID - 23682
TI - Density near zero
JO - Sahand Communications in Mathematical Analysis
JA - SCMA
LA - en
SN - 2322-5807
AU - Bayatmanesh, Elham
AU - Akbari Tootkaboni, Mohammad
AD - Department of Mathematics, Faculty of Basic Science, Shahed University, Tehran, Iran.
Y1 - 2018
PY - 2018
VL - 09
IS - 1
SP - 33
EP - 43
KW - The Stone-Cech compactification
KW - Density
KW - Piecewise syndetic set near zero
DO - 10.22130/scma.2018.23682
N2 - Let $S$ be a dense subsemigroup of $(0,+infty)$. In this paper, we state definition of thick near zero, and also we will introduce a definition that is equivalent to the definition of piecewise syndetic near zero which presented by Hindman and Leader in [6]. We define density near zero for subsets of $S$ by a collection of nonempty finite subsets of $S$ and we investigate the conditions under these concepts.
UR - http://scma.maragheh.ac.ir/article_23682.html
L1 - http://scma.maragheh.ac.ir/article_23682_545b6075235df500f5ed73aa31024524.pdf
ER -