Chef Goes to the Cinema

Chef lives in Chefcity. Chefcity can be represented as a straight line with Chef's house at point 0 on this line. There is an infinite number of subway stations in Chefcity, numbered by positive integers. The first station is located at point 1 and for each i ≥ 1, the distance between stations i and i+1 is equal to i+1. (Station i+1 is always located at a higher coordinate than station i, i.e., th