$n\ge 8\,\Rightarrow\, n = 3j + 5k\ $ for $\,j,k,n\in \Bbb N$
11359
Determine the Set of a Sum of Numbers
39965
Partition of $\mathbb{Z}_8$ into cosets of Ker(θ)
53162
$13\mid4^{2n+1}+3^{n+2}$
27544
With $a,\ b,\ m,\ n\in \mathbb{Z}$. Show that if ${\rm gcd}(m,n)=1$, then ${\rm gcd}(ma+nb,mn)={\rm gcd}(a,n){\rm gcd}(b,m)$
116722
Simplifying $\big(\sum_{i=0}^n\binom{k}{i}\binom{M-k}{n-i}\frac{k-i}{M-n}\big)/{\binom{M}{n}}$
27610
Given the permutation $\sigma=\left(\begin{array}{ccccc} 1&2&3&4&5\\ 3&1&2&5&4 \end{array}\right)$
148774
show elements of order 15 in $S_8$ satisfy a relation
71564
Combinatorial proof of identity involving central binomial coefficients
106441
Find the value of $\binom{2000}{2} + \binom{2000}{5} + \binom{2000}{8} + \cdots \binom{2000}{2000}$
119146
How to solve $n < 2^{n/8}$ for $n$?
67926
$S_n$ is generated by elements of the form $(1k)$
107964
Simple combinatorics problem.
103504
Weird $3^n$ in an identity to be combinatorially proved
90789
Use induction to prove that that $8^{n} | (4n)!$ for all positive integers $n$
72557
Prove that $T(n) = T(n/3) + T2n/3) + 5n$ is $O(n log n)$
39642
Efficient way to find $[\mathbb{Q}(\sqrt{5}, \sqrt{3}, \sqrt{2}): \mathbb{Q}(\sqrt{3}, \sqrt{2})]$
125499
Find this sequence $a_{i}$ such $\gcd{(a_{i},a_{j})}=\gcd{(i,j)}$