Skip to main content
7 events
when toggle format what by license comment
S Feb 3, 2016 at 10:46 history edited András Bátkai
I add a tag
S Feb 3, 2016 at 10:46 history suggested Ali Taghavi
I add a tag
Feb 3, 2016 at 10:40 comment added Gro-Tsen The keyword you want to search for is "Baire class 1" functions. See for example Kechris's Classical Descriptive Set Theory (Springer GTM 156), §24.B. One characterization is that $f\colon\mathbb{R}\to\mathbb{R}$ is pointwise limit of continuous functions iff $f^{-1}(U)$ is a countable union of closed sets for every open set $U$ (op. cit., 24.10). Its set of continuous points is then a comeager (hence dense) $G_\delta$ (op. cit., 24.14).
Feb 3, 2016 at 10:14 review Suggested edits
S Feb 3, 2016 at 10:46
Feb 3, 2016 at 10:10 answer added Ali Taghavi timeline score: 6
Feb 3, 2016 at 9:21 answer added smyrlis timeline score: 6
Feb 3, 2016 at 9:14 history asked Bazin CC BY-SA 3.0