Find the highest power of $2$ which divides the numerator of $H_{k}=1+\frac{1}{3}+\frac{1}{5}+\cdots+\frac{1}{2k-1}$
7109
2-adic valuation of odd harmonic sums
151179
Finding the value of $\sum k/3^k$
5841
Proving prime $p$ divides $\binom{p}{k}$ for $k\in\{1,\ldots,p-1\}$
13617
Evaluating the nested radical $ \sqrt{1 + 2 \sqrt{1 + 3 \sqrt{1 + \cdots}}} $.
151692
When does $2^n-1$ divide $3^n-1$?
49096
How can I prove $5^{3^n}+1$ is divisible by $3^{n+1}$
117468
$o(g^{k})=\frac{o(g)}{\gcd(o(g),k)}$ order of a power of a group element.
26607
The idea behind the sum of powers of 2
99453
Sum of $k$-th powers
125512
Doubt regarding divisibility of the expression: $1^{101}+2^{101} \cdot \cdot \cdot +2016^{101}$
157771
Nested exponent modulus, $2^{2^{517}} \pmod {23}$
151961
Irreducibility of $x^{p(p-1)}+x^{p(p-2)}+\cdots+x^p+1$ over $\mathbb Q$
99908
When does $120$ divide $n^5 - n$
91921
Divisibility of $n\cdot2^n+1$ by 3.
34192
Solve $x^{5} \equiv 2$ mod $221\ $ [Taking modular $k$'th roots if unique]
103616
Distance between powers of 2 and 3
35326
There are infinitely many $N$ such that $\frac{N}{2}$ is a perfect square, $\frac{N}{3}$ is a perfect cube, and $\frac{N}{5}$ is a perfect fifth power