Find the number of subsets? (There is no proper solution for the duplicate question, please provide proper proof )
47123
Suppose that a set has an odd number of elements. Explain why half of the subsets will have an odd number of elements
114370
I want to figure out how many Topologies are in the set X
70278
$A\subseteq B\to C\setminus B\subseteq C\setminus A\,$ -- how to prove this?
82207
Number of Pairs of Subsets
28453
Finding all partitions of a set
106325
Question about Cardinality
2900
How many $3$-subsets of $\{1,2,\ldots,10\}$ contain at least one even and one odd integer?
114262
Find the cardinality of the following set $S_n=\{(x,y)|x^2+y^2=n, \text{where }x,y,n \in \mathbb Z\text{ and }n\geq0 \}$
85099
How many subsets of $\mathbb{N}$ have the same cardinality as $\mathbb{N}$?
150281
Am I on the right track to figure out this combinatorics problem?
73350
Geometric solution to find a Set of totally ordered Subsets of $ \mathbb{N} $ is uncountable
35362
Number of equivalence relations on a set
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?
36486
Finding the total number of set-bits from 1 to n
57822
Number of ways to choose two disjoint subsets of a set
65768
What is the cardinality of the set of the empty set?
119084
How many ordered pairs $(A,B)$ they are if $A$ and $B$ are subsets of $\{ 1,2,3,4,5 \}$ such that $A \cap B = \{1\}$?