Introducing ordered pairs in an axiomatic way
66636
Problems with introducing ordered pairs axiomatically
32081
The dual version of trichotomy of cardinality without AC
87451
Construction of matrices under ZFC axioms
22482
How can an ordered pair be expressed as a set?
137907
Composing functors with natural transformations
1508
How do I prove that a definition of an ordered pair does not satisfy the required property?
4383
Finitely generated monoids - how to show that there is not first order set axiomatizing them.
132287
Axiom of Choice and Right Inverse
56440
Cartesian products and families
102202
The smallest infinity and the axiom of choice
81509
The cardinality of a countable union of countable sets, without the axiom of choice
36325
Embedding ordinals in $\mathbb{Q}$
3217
Construction of uncountably many non-isomorphic linear (total) orderings of natural numbers
69043
The equivalence relation generated by a relation
4002
A function that accepts a pair or a list of pairs
78290
Countable axiom of choice: why you can't prove it from just ZF
20252
The Axiom of Choice and the Cartesian Product.