How many subsets with an even number of elements?
21152
Exactly half of the elements of $\mathcal{P}(A)$ are odd-sized
44214
The number of subsets of a set of cardinality $n$
150430
Let $S={1, 2, 3, 4, ....., 2070}$ find the number of subsets of $S$ whose sum of elements in $S$ is divisible by 9
146098
Number of nonempty subsets of a set with $n$ elements
1643
Number of reflexive relations defined on a set A with n elements
60309
Let X be a subset of {1,2,...,2014}...
156242
As many even numbers as natural numbers.
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...
64519
Subsets of a list
132605
Finding the number of subsets of a set such that an element divides the succeeding element.
123626
Prove that even $n$ can be partitioned to $\frac n2$ edges
45448
Minimum number of $k$-partitions of a set of size $n$ to enumerate all $n \choose k$ combinations
135698
Count subsets whose cardinalities are congruent to 0, 1 and 2 modulo 3 respectively
47123
Suppose that a set has an odd number of elements. Explain why half of the subsets will have an odd number of elements
104010
The number of partitions of $n$ into distinct parts equals the number of partitions of $n$ into odd parts
31969
Partition of N into infinite number of infinite disjoint sets?
35648
How many permutations of the set n={1,2,3,3,3,4,4,5} are possible without any consecutive identical elements?