Polynomial Tau-Functions of the n-th Sawada–Kotera Hierarchy

We give a review of the B-type Kadomtsev–Petviashvili (BKP) hierarchy and find all polynomial tau-functions of the n-th reduced BKP hierarchy (=n-th Sawada–Kotera hierarchy). The name comes from the fact that, for n=3, the simplest equation of the hierarchy is the famous Sawada–Kotera equation.