I don't think this is one of those cases though. See Terry Tao's take on a similar problem about when to tie your shoelace: https://terrytao.wordpress.com/2008/

I don't think this is one of those cases though. See Terry Tao's take on a similar problem about when to tie your shoelace: https://terrytao.wordpress.com/2008/12/09/an-airport-inspired-puzzle/ https://terrytao.wordpress.com/2008/12/09/an-airport-inspire...