Find the cardinality of the set $\{ X \subset \mathbb{N} : |X| = \aleph_0\}$
85099
How many subsets of $\mathbb{N}$ have the same cardinality as $\mathbb{N}$?
102972
Cardinality of $\mathbb{R}^\mathbb{R}$ by diagonal argument
30519
"Real" cardinality, say, $\aleph_\pi$?
10839
Problem in Cardinality and Order
35043
Cardinality of a set A is strictly less than the cardinality of the power set of A
132537
Class of sets of a given infinite cardinality
146436
Cardinality of the set of bijective functions on $\mathbb{N}$?
109968
Let $X= \{ A \subset \mathbb{N} : \mathbb{N} \backslash A \text{ is finite}\}$. What is the cardinality of $X$? Prove it.
41783
Cardinality of the Cartesian Product of Two Equinumerous Infinite Sets
62687
Proving Cardinality of Cosets in Abstract Algebra
65953
Cardinality of the set of differentiable functions
16553
Cardinality of the set of all total orders on $\Bbb{N}$
150064
Cardinality of "$x-y\in\Bbb Q$"-equivalence class of $1/\sqrt2$
89167
Cardinality of equivalence relations in $\mathbb{N}$
21782
Is $\aleph_0 = \mathbb{N}$?
149673
Cardinality of an infinite union of finite sets
20085
What's the cardinality of all sequences with coefficients in an infinite set?