An ultrafilter approach to Jin’s theorem
نویسندگان
چکیده
منابع مشابه
An Ultrafilter Approach to Jin’s Theorem
It is well known and not difficult to prove that if C ⊆ Z has positive upper Banach density, the set of differences C −C is syndetic, i.e. the length of gaps is uniformly bounded. More surprisingly, Renling Jin showed that whenever A and B have positive upper Banach density, then A − B is piecewise syndetic. Jin’s result follows trivially from the first statement provided that B has large inter...
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ژورنال
عنوان ژورنال: Israel Journal of Mathematics
سال: 2011
ISSN: 0021-2172,1565-8511
DOI: 10.1007/s11856-011-0114-5