https://riemannhypothesis.blog/tags/stack-exchange/ Recent content in Stack Exchange on Understanding the Riemann Hypothesis Hugo -- gohugo.io en markus@recommend.games (Markus Shepherd) markus@recommend.games (Markus Shepherd) Wed, 23 Sep 2015 20:24:52 +0000 https://riemannhypothesis.blog/2015/09/prime-generating-sequences/ Wed, 23 Sep 2015 20:24:52 +0000markus@recommend.games (Markus Shepherd) https://riemannhypothesis.blog/2015/09/prime-generating-sequences/ A couple of months ago (really, a long, long time ago) I found an interesting question on Mathematics Stack Exchange (another site to effectively waste away hours of your life). It reminded me of my Bachelor’s thesis (which I wrote a really, really long time ago) about the sequence \[ g_n=\mathrm{gcd}(n,a_{n-1})=(n,a_{n-1}) \quad\text{for}\quad n>1, \] where \(a_1=7\) and \[ a_n=a_{n-1}+g_n. \] Here, \(\mathrm{gcd}(a,b)=(a,b)\) stands for the greatest common divisor,1 i.e., the largest integer \(d\) that divides both \(a\) and \(b\).