Proving the set of finite subsets of $\mathbb{N}$ is countably infinite
41661
Show that the set of all finite subsets of $\mathbb{N}$ is countable.
99656
Prove that the set of all algebraic numbers is countable
148992
A finite set is closed
102113
Proof that the number of proofs is countably infinite
118595
Proving that a set is countable by finding a bijection
71922
Prove Uncountable set minus a countable set is uncountable
97064
Dense set in an infinite cofinite space
139247
Real Analysis - Prove a set is countable
79490
Proving the set of points at which a function diverges to $\infty$ is countable
128437
How to prove that a finite set is countable
44974
Infinite set and countable subsets
139078
Infinite partition of $\mathbb N$ by infinite subsets
23442
Cardinality of the union of infinite and countable sets
134071
If A is a finite set and B is an infinite set, then B\A is an infinite set
111008
Show that $X $ is a infinite set ,it is connected in the finite complement topology?
6523
Prove that the space has a countable dense subset
147013
Subset of a finite set is finite