Example of open cover of (0,1) which has no finite subcover
55374
Cover of (0,1) with no finite subcover & Open sets of compact function spaces
125604
Proof that $\mathbb{Z}$ has no zero divisors
136538
How can I show that a bijection between $[0,1)$ and $(0,1)$ cannot be continuous?
146306
A continuous surjective function from $(0,1]$ onto $[0,1]$
29653
Show that $xy=0$ is a variety but not a manifold
47537
Open nonempty subset of irreducible variety over $k$ has the same Krull dimension as the whole variety?
86724
Example of a non-zero module that has no associated primes
15128
Example of non-decomposable ideal
16649
Topological space with countable open cover $\{U_\alpha\} $ with each $U_\alpha$ second-countable, is second countable
101095
Constructing an example s.t. $\operatorname{Hom}_R(M,N)$ is not finitely generated
131460
Example of finite field extension where root not separable
121626
Every open cover of the real numbers has a countable subcover (Lindelöf's lemma)
150605
Existence of a regular uncountable $\aleph_{\alpha}$ without $\mathsf{AC}$
93389
Uncountable sets of Hausdorff dimension zero
113385
Example of $f,g: [0,1]\to[0,1]$ and Riemann-integrable, but $g\circ f$ is not?
39129
Simplest Example of a Poset that is not a Lattice
144572
Proof that ideals in $C[0,1]$ are of the form $M_c$ that should not involve Zorn's Lemma