Timeline for Examples of Sets with Positive Upper Density
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 21, 2018 at 13:12 | vote | accept | john mangual | ||
| Jul 24, 2016 at 11:23 | answer | added | Jan-Christoph Schlage-Puchta | timeline score: 2 | |
| Jul 21, 2016 at 19:40 | comment | added | Anthony Quas | Here's another nice example: the set of numbers that have an even number of 1's in their binary expansion. This is related to the (Prouhet)-Thue-Morse sequence. | |
| Jul 21, 2016 at 18:51 | comment | added | john mangual | my apologies, yes $A \subseteq \mathbb{Z}$. I mean let $f: \mathbb{R} \to [-1,1]$ be any reasonable bounded oscillating function, and chose the Bohr set of $\{f \geq 0\} \cap \mathbb{Z}$. | |
| Jul 21, 2016 at 18:50 | answer | added | coudy | timeline score: 4 | |
| Jul 21, 2016 at 18:45 | comment | added | Stanley Yao Xiao | Are you looking for subsets of positive integers? I assume you also want examples where the upper density is positive but the density is not defined? | |
| Jul 21, 2016 at 18:28 | history | asked | john mangual | CC BY-SA 3.0 |