query: Counter Example of $\cup$ A$_i$ is not compact.
positive_passages.docid: 153573
positive_passages.text: Counter Example for the union of any number of compact sets is compact in T2-spaces
negative_passages.docid: 9268
negative_passages.text: Proving that the Union of Two Compact Sets is Compact
negative_passages.docid: 95728
negative_passages.text: The union of growing circles is not homeomorphic to wedge sum of circles
negative_passages.docid: 101095
negative_passages.text: Constructing an example s.t. $\operatorname{Hom}_R(M,N)$ is not finitely generated
negative_passages.docid: 111064
negative_passages.text: Example of a bounded lattice that is NOT complete
negative_passages.docid: 3896
negative_passages.text: A closed set in $(A, \mathcal T_A)$ that is not closed in $(X, \mathcal T)$
negative_passages.docid: 47231
negative_passages.text: The space $C^0([0;1],\mathbb{R})$ of all continuous, real-valued functions on $[0,1]$ is not reflexive.
negative_passages.docid: 47251
negative_passages.text: Non-compactness of $\mathbb{R}$ with the cocountable topology
negative_passages.docid: 115350
negative_passages.text: An example of a Banach space isomorphic but not isometric to a dual Banach space
negative_passages.docid: 19996
negative_passages.text: Example where union of increasing sigma algebras is not a sigma algebra
negative_passages.docid: 119831
negative_passages.text: bounded operator $T$ is not compact then there exists an orthonormal sequence $e_n$ and $d>0$ such that $\|T(e_n)\|>d$ for all $n\in\Bbb{N}$?
negative_passages.docid: 129227
negative_passages.text: An example of neither open nor closed set
negative_passages.docid: 13961
negative_passages.text: An example of a lattice that's not totally ordered
negative_passages.docid: 47937
negative_passages.text: Example of a Borel set that is neither $F_\sigma$ nor $G_\delta$
negative_passages.docid: 31002
negative_passages.text: Proving that the unit ball in $\ell^2(\mathbb{N})$ is non-compact
negative_passages.docid: 25874
negative_passages.text: Showing that a certain map is not flat by explicit counterexample
negative_passages.docid: 67383
negative_passages.text: Prove that $G'$ is not planar.