How many subsets does a set $S$ with $n$ elements have?
112049
How many elements does $\mathcal{P}(A)$ have?
132605
Finding the number of subsets of a set such that an element divides the succeeding element.
45448
Minimum number of $k$-partitions of a set of size $n$ to enumerate all $n \choose k$ combinations
5118
Show that $n ≤ 100$ if $ \{A_1,A_2,... ,A_n\}$ is a set of distinct $3$-element subsets of $\{1, 2,... , 36\}$ such that...
75966
Prove that if $A$ is a set with $m$ elements, $B$ is a set with $n$ elements, and $A \cap B = \emptyset$, then $A \cup B$ has $m+n$ elements.
74860
Why is the empty set a subset of every set?
16056
Is empty set element of every set if it is subset of every set?
101669
Cardinality of the Set of all finite subset of $\mathbb{R}$
4776
Prove that the power set of an $n$-element set contains $2^n$ elements
31969
Partition of N into infinite number of infinite disjoint sets?
1409
Proving that the given set has at most $2^{n-1}$ elements
64519
Subsets of a list
147484
For a set with N members, what is the number of set partitions in which each subset is either of size 1 or 2?
134921
Find the number of all subsets of $\{1, 2, \ldots,2015\}$ with $n$ elements such that the sum of the elements in the subset is divisible by 5
108275
How do I count the subsets of a set whose number of elements is divisible by 3? 4?
44214
The number of subsets of a set of cardinality $n$
2900
How many $3$-subsets of $\{1,2,\ldots,10\}$ contain at least one even and one odd integer?