Enumerative Aspects of Nullstellensatz Certificates
  Using polynomial equations to model combinatorial problems has been a popular tool both in computational combinatorics as well as an approach to proving new theorems. In this paper, we look at several combinatorics problems modeled by systems of polynomial equations satisfying special properties. If the equations are infeasible, Hilbert's Nullstellensatz gives a certificate of this fact. These certificates have been studied and exhibit combinatorial meaning. In this paper, we generalize some known results and show that the Nullstellensatz certificate can be viewed as enumerating combinatorial structures. As such, Gr\"obner basis algorithms for solving these decision problems may implicitly be solving the enumeration problem as well. 
Bart Sevenster, Jacob Turner
math.CO math.AC