Given positive integers $a$, $b$ and $c$, I'd like to ask whether we may adopt some variant of the Euclidean algorithm to calculate $\gcd(c^a+1,c^b+1)$ fast?
Asked
Active
Viewed 70 times
1
-
Welcome to MSE. You'll find that simple "Here's the statement of my exercise, solve it for me" posts will be poorly received. What is better is for you to add context: What you understand about the problem, what you've tried so far, etc. Something to both show you are part of the learning experience and to help us guide you to the appropriate help. You can consult this link for further guidance. – B. Mehta Jul 29 '18 at 17:53
-
Start from here. – Jyrki Lahtonen Jul 29 '18 at 17:54
-
4Use of Approach0 is highly recommended when you suspect that the question has already been asked and answered. – Jyrki Lahtonen Jul 29 '18 at 17:56
-
1@JyrkiLahtonen I didn't know about Approach0. Thanks a lot! – saulspatz Jul 29 '18 at 18:08
-
@JyrkiLahtonen I think this post probably solves the problem, but I'd like to ask what the function $v_2$ is? – Hang Wu Jul 29 '18 at 18:59
-
1I find that $v_2(n)$ is the 2-adic order of $2n$. – Hang Wu Jul 29 '18 at 19:47