| Title: | Maximal upper asymptotic density of sets of integers with missing differences from a given set (English) | 
| Author: | Pandey, Ram Krishna | 
| Language: | English | 
| Journal: | Mathematica Bohemica | 
| ISSN: | 0862-7959 (print) | 
| ISSN: | 2464-7136 (online) | 
| Volume: | 140 | 
| Issue: | 1 | 
| Year: | 2015 | 
| Pages: | 53-69 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | Let $M$ be a given nonempty set of positive integers and $S$ any set of nonnegative integers. Let $\overline \delta (S)$ denote the upper asymptotic density of $S$. We consider the problem of finding \[\mu (M):=\sup _{S}\overline \delta (S),\] where the supremum is taken over all sets $S$ satisfying that for each $a,b\in S$, $a-b \notin M.$ In this paper we discuss the values and bounds of $\mu (M)$ where $M = \{a,b,a+nb\}$ for all even integers and for all sufficiently large odd integers $n$ with $a<b$ and $\gcd (a,b)=1.$ (English) | 
| Keyword: | upper asymptotic density | 
| Keyword: | maximal density | 
| MSC: | 11B05 | 
| idZBL: | Zbl 06433698 | 
| idMR: | MR3324419 | 
| DOI: | 10.21136/MB.2015.144179 | 
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| Date available: | 2015-03-09T17:40:37Z | 
| Last updated: | 2020-07-29 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/144179 | 
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