Find the greatest common divisor of $2^{2004}-1$ and $2^{2002}-1$.
6012
Prove that $\gcd(a^n - 1, a^m - 1) = a^{\gcd(n, m)} - 1$
24864
$ \Big(\dfrac{x^7+y^7+z^7}{7}\Big)^2=\Big(\dfrac{x^5+y^5+z^5}{5}\Big)^2\cdot\Big(\dfrac{x^4+y^4+z^4}{2}\Big) $
116175
Show that $\gcd(3k+2,5k+3)=1$
125737
GCD( LCM(a,b) , LCM(a,c) ) = LCM(b, GCD(b,c)) , why?
147665
$a_1=3;\ a_{n+1}=3^{a_n}$; find $a_{2004}\bmod100$
110444
Finding out the number of divisors
46555
How to calculate GCD of Gaussian integers?
120459
Problem with finding the GCD in the Field of Polynomials mod p
27859
least common multiple of $\{1,2,...,n\}$ is bigger than $2^{n-1}$
110695
Divisor of $2^{2^n} + 1$ modulus $2^{n+1}$
111555
Find $a,b \in \mathbb{N}$ with $\mathrm{lcm}(a,b)=12\gcd(a,b)\,$ and $\,a\bmod b = 5$
105832
prove that if $\gcd(a,b)=1$ then $\gcd(a^2, b^2)=1$
43155
Cyclotomic Polynomials and GCD
94914
Concise proof that every common divisor divides GCD without Bezout's identity?
14693
$d = \gcd(c,m),\ ac≡bc\pmod{\! m}\Rightarrow a≡b\pmod {\!m/d}\ $ [Congruence Cancellation & Division Rule]
112631
Prove that if $d$ divides $n$, then $2^d -1$ divides $2^n -1$
85688
How to show $\gcd(ac, bd) = \gcd(a,d) * \gcd(b,c)$