How to write numbers in the language of first-order set theory.
119982
how to express the set of natural numbers in ZFC
127233
Cardinality of order types in $\mathbb{N}$
32441
How to prove or disprove statements about sets
120712
Is there a way to define the "size" of an infinite set that takes into account "intuitive" differences between sets?
141299
Alternative set theories
73850
Cardinality of set of functions
117047
exponentiation of cardinal number
54497
Set Notation - Inclusion and Proper Inclusion
4383
Finitely generated monoids - how to show that there is not first order set axiomatizing them.
125950
Proof strategy involving first order logic for existential quantification at very beginning
33851
Generalizing a sequence.
59385
Are there number systems corresponding to higher cardinalities than the real numbers?
111954
Computing the cardinality of a combinatorial set
3119
Distribution of Universal Quantifiers
151994
Why do first order languages have at most countably many symbols?
102202
The smallest infinity and the axiom of choice
32081
The dual version of trichotomy of cardinality without AC