Removal of a countable collection of pairwise disjoint closed balls from the plane,and path connectedness
114990
Is the complement of countably many disjoint closed disks path connected?
6491
Not every open set in $\mathbb{R}^n$, for $n\geq2$, is a disjoint union of countable open balls.
111954
Computing the cardinality of a combinatorial set
102323
Nice neighborhoods of each "piece" in a manifold connected sum
43845
Partitioning the edges of $K_n$ into $\lfloor \frac n6 \rfloor$ planar subgraphs
116538
Proof of Connected Diagrams
70645
Borel set preserved by continuous map
36184
Countability of disjoint intervals
58508
Number of ways to pair off $2n$ points such that no chords intersect
133938
Connectedness of the Hausdorff distance.
97627
filling an occluded plane with the smallest number of rectangles
128987
A collection of pairwise disjoint open intervals must be countable
70143
Mutually exclusive countable subsets of a countable set
44623
Closed set as a countable intersection of open sets
46469
$n$ Lines in the Plane
36315
Is $[0,1]$ a countable disjoint union of closed sets?
121095
Is convex hull of a finite set of points in $\mathbb R^2$ closed?