In this paper we consider the cocircuit graph G M of an oriented matroid M, the 1-skeleton of the cell complex W formed by the span of the cocircuits of M. In general,W is not determined by G M.… (More)

Dn−1 = I −A · Dn−1 + Dn−2 = cn−1 I −A · Dn−2 + Dn−3 = cn−2 I .. .. .. −A · D1 + D0 = c1 I −A · D0 = c0 I Finally, by multiplying the first equation by An, the second by A, and so on, up to the last… (More)

We introduce a new family of hyperplane arrangements in dimension n ≥ 3 that includes both the Shi arrangement and the Ish arrangement. We prove that all the members of this family have the same… (More)

We define a bijection between the set of parking functions of size n and the set of rooted (labeled) forests with n vertices for which the number of “probes” of the function is the number of… (More)

We consider the set Z0 of non-negative integers endowed with a distance d defined as follows: given x, y ∈ Z0 , d(x, y) is, in binary notation, the result of performing, digit by digit, the “exlusive… (More)