elementary number theory gcd lcm
107095
Prove $\gcd(a,b) \gcd(a,c) \gcd(b,c) \,\text{lcm} (a,b,c)^2=$ $\text{lcm}(a,b)\,\text{lcm}(a,c) \,\text{lcm}(b,c) \gcd(a,b,c)^2$
21288
For integers $a$ and $b$, $ab=\text{lcm}(a,b)\cdot\text{hcf}(a,b)$
97196
$k^{\phi(l)} + l^{\phi(k)} \equiv1\pmod{lk}\,$ if $\,\gcd(l,k)=1$
50249
Pairs of numbers with a given LCM
135086
GCD of two numbers divided by their greatest common divisor is 1
153647
Elementary number theory and quadratic
20574
Understanding the proof for $\gcd (F_n, F_{n+k}) = 1$ where $F_n$ is a Fermat number
64063
GCD domain is LCM domain
117098
Properties of the greatest common divisor: $\gcd(a, b) = \gcd(a, b-a)$ and $\gcd(a, b) = \gcd(a, b \text{ mod } a)$
19164
On the GCD of a Pair of Fermat Numbers
92024
Elementary number theory - prerequisites
63965
How can I compute the sum of $ {m\over\gcd(m,n)}$?
121280
Proving that $a \mathbb{Z} \cap b\mathbb{Z} = \operatorname{lcm}(a,b)\mathbb Z$
139833
Prove that $\gcd(M, N)\times \mbox{lcm}(M, N) = M \times N$.
148108
Let $L=\operatorname{lcm}(o(a), o(b))$ and prove that $(ab)^L =e$.
142693
$\gcd(a,b) = \gcd(a + b, \mathrm{lcm}[a,b])$
59462
Prove that $n!=\prod_{k=1}^n \operatorname{lcm}(1,2,...,\lfloor n/k \rfloor)$ for any $n \in \mathbb N$