Abstract We analyze Nash games played among leaders of Stackelberg games (NASP). We show it is $$\Sigma^p_2$$-hard to decide if the game has a mixed-strategy Nash equilibrium (MNE), even when there are only two leaders and each leader has one follower. We provide a finite…

At Polytechnique, Ph.D students are required to take a reasonable (depending on your standard) number of courses before jumping in the rainbowy world of research. As Optimizer, I feel compelled to be a bit lazy, and therefore I produced some quick references for the basic I…

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…

Abstract Single-elimination tournaments are the standard paradigm both for the main tennis professional associations. Schedules are generated by allocating first seeded and then unseeded players with seeds prevented from encountering each other early in the competition. B…