Does the empty set have a supremum? Is it $-\infty$?
55995
Why is the supremum of the empty set $-\infty$ and the infimum $\infty$?
133886
Existence of increasing sequence $\{x_n\}\subset S$ with $\lim_{n\to\infty}x_n=\sup S$
82315
is an empty set an element of {empty set}
66441
Prove that $|x|<1$ implies that $\lim_{n \to \infty} x^n=0$
47820
How can I show a supremum of a set is also its limit point?
43462
Disprove $\mathcal{P}(A\Delta B) \setminus \{\emptyset\} = \mathcal{P}(A) \Delta\mathcal{P}(B) $. Is my proof good?
5105
Alternative definition of $\|f\|_{\infty}$ as the smallest of all numbers of the form $\sup\{|g(x)| : x \in X \}$, where $f = g$ almost everywhere
35644
Find the supremum of the following set
11405
If a nonempty set of real numbers is open and closed, is it $\mathbb{R}$? Why/Why not?
92249
Every finite set contains its supremum: proof improvement.
125502
Empty set literal?
111475
Uniform convergence and the supremum theorem
58594
Is the empty set a subset of itself?
107215
Is $\emptyset \in \emptyset$ or $\emptyset \subseteq \emptyset$?
50846
Is a set without limit points necessarily closed?
858
Is $\{\emptyset\}$ a subset of $\{\{\emptyset\}\}$?
58285
Is it true that if $X$ is connected, then for every nonempty proper subset $A$ of $X$, we have $\mathbf{Bd} \ne \emptyset$