The Dartmouth Math Society will be meeting at 6:30PM today with free PIZZA and drinks, followed by a talk by Professor Peter Doyle. He'll be discussing the following question from the 1986 International Mathematical Olympiad: "To each vertex of a regular pentagon an integer is assigned in such a way that the sum of all five numbers is positive. If three consecutive vertices are assigned the numbers x, y, z respectively and y < 0 then the following operation is allowed: the numbers x, y, z are replaced by x+y, -y, z+y respectively. Such an operation is performed repeatedly as long as at least one of the five numbers is negative. Determine whether this procedure necessarily comes to and end after a finite number of steps." Hope to see you there!