Nash Equilibria with Derangement Degree Probabilities

Abstract

We prove for every $n\ge 4$ the existence of an $n$-player game in normal form with integer payoffs that has a unique Nash equilibrium, which is fully mixed. In the equilibrium, each probability weight is an algebraic number of degree $!n$ (the derangement number), and its minimal polynomial has Galois group $S_{!n}$ and $!n+1$ nonzero coefficients.