In joint work with Papa Sissokho, we addressed the problem of counting the number of points in the complement of the complete hyperplane arrangement over the ring of integers mod n. This problem is considered intractable, and our recent work on this problem has led to several interesting connections to other mathematical problems, including the Hadamard problem, zero-sum free sequences, classifying Mathieu-Zhao subspaces, and the distribution of the values of the Euler-phi function. I will present an overview of this research.
