Abstract Motivated by international energy trade between countries with profit-maximizing domestic producers, we analyze Nash games played among leaders of Stackelberg games (NASP). We prove it is both \(\Sigma^p_2\)-hard to decide if the game has a pure-strategy (PNE) or…

In conferences held at the Oberwolfach Institute, participants usually dine together in a room witg tables of different sizes, and each participant has an assigned seat. Gerhard Ringel asked whether there exists a seating arrangement for an odd number \(v\) of people and…

At Polytechnique, we -- Ph.D students -- are required to take a few courses before technically levelling up to Ph.D. candidates. As Optimizer, I feel compelled to be a bit lazy, and I always seek for something quick and clear. Plus, since I am also first-in-class in terms o…