Finding the number of elements of order 2 in $D_{n}$
94420
Dihedral group - elements of order $2$
122959
How is number of conjugacy class related to the order of a group?
15000
Show that number of elements in $(Z/nZ)^*$ is $\phi (n)$
19599
$ d(x_n,y_n) \to d(x,y)$ if $x_n\to x$ and $y_n \to y$
1712
$ d_1,d_2\mid n\iff {\rm lcm}(d_1,d_2)\mid n\ $ [LCM Universal Property]
140087
The number of divisors
77547
Find integers $a,b,c,d$ such that
45314
Conjugacy classes of D2n?
48502
number of ordered pairs of integers $(x,y)$ satisfying the equation
18881
Number of elements of order $7$ in a group
26343
Number of certain (0,1)-matrices, Stanley's Enumerative Combinatorics
155831
What are the total number of ordered permutations of a list of elements (possibly repeated)?
136848
Find the number of nonzero elements
117862
Number of partitions of an $n$-element set into $k$ classes
121706
Show $\text{det}(A)$ is divisible by $2^{n-1}$
26398
Group of even order contains an element of order 2
66842
Number of $n^2\times n^2$ permutation matrices with a 1 in each $n\times n$ subgrid