Let S be the set of stars in our galaxy. There is same number subsets as functions f : S --> {a,b}?
66948
Proving question on sets
7785
Cardinality of sum-set
14711
set theoretic function, products of sets (product versus Cartesian product)
55924
How many distinct functions can be defined from set A to B?
64583
Number of surjective functions from A to B
65316
Explaining Infinite Sets and The Fault in Our Stars
149382
Prove that $(0,1) \subseteq\mathbb R$ and $(4,10) \subseteq\mathbb R$ have the same cardinality.
114262
Find the cardinality of the following set $S_n=\{(x,y)|x^2+y^2=n, \text{where }x,y,n \in \mathbb Z\text{ and }n\geq0 \}$
7733
If A is infinite, does there have to exist a subset of A that is equivalent to A?
13273
Cardinality of the set of all real functions of real variable
142267
If two sets have the same cardinality, then so do their power sets. Converse can't be answered?
146436
Cardinality of the set of bijective functions on $\mathbb{N}$?
139039
Stars and Bars Combinatorics Problem
272
Cantor Sets/nonempty/cardinality
35362
Number of equivalence relations on a set
70034
Showing that this set of functions is a group.
89712
For every set $A$, the empty set is a subset of $A$. The empty set is a set. Therefore, the empty set has a cardinality $\geq 1\ldots$