Explicit Hilbert-Kunz functions of 2 x 2 determinantal rings

Marcus Robinson, Irena Swanson

Let $k[X]=k[x_{i,j}:i=1,...,m;j=1,...,n]$ be the polynomial ring in $mn$ variables $x_{i,j}$ over a field $k$ of arbitrary characteristic. Denote by $I_2(X)$ the ideal g…