More than a 0-point

Flašková, Jana. "More than a 0-point." Commentationes Mathematicae Universitatis Carolinae 47.4 (2006): 617-621. <http://eudml.org/doc/249836>.

@article{Flašková2006,
abstract = { We construct in ZFC an ultrafilter $U \in \mathbb \{N\}^\{\ast \}$ such that for every one-to-one function $f : \mathbb \{N\}\rightarrow \mathbb \{N\}$ there exists $U\in U$ with $f[U]$ in the summable ideal, i.e. the sum of reciprocals of its elements converges. This strengthens Gryzlov’s result concerning the existence of $0$-points.},
author = {Flašková, Jana},
journal = {Commentationes Mathematicae Universitatis Carolinae},
keywords = {ultrafilter; $0$-point; summable ideal; linked family; ultrafilter; 0-point; summable ideal; linked family},
language = {eng},
number = {4},
pages = {617-621},
publisher = {Charles University in Prague, Faculty of Mathematics and Physics},
title = {More than a 0-point},
url = {http://eudml.org/doc/249836},
volume = {47},
year = {2006},
}

TY - JOUR
AU - Flašková, Jana
TI - More than a 0-point
JO - Commentationes Mathematicae Universitatis Carolinae
PY - 2006
PB - Charles University in Prague, Faculty of Mathematics and Physics
VL - 47
IS - 4
SP - 617
EP - 621
AB - We construct in ZFC an ultrafilter $U \in \mathbb {N}^{\ast }$ such that for every one-to-one function $f : \mathbb {N}\rightarrow \mathbb {N}$ there exists $U\in U$ with $f[U]$ in the summable ideal, i.e. the sum of reciprocals of its elements converges. This strengthens Gryzlov’s result concerning the existence of $0$-points.
LA - eng
KW - ultrafilter; $0$-point; summable ideal; linked family; ultrafilter; 0-point; summable ideal; linked family
UR - http://eudml.org/doc/249836
ER -