# Extremal matrices for the Bruhat-graph order

@article{Fernandes2020ExtremalMF, title={Extremal matrices for the Bruhat-graph order}, author={Ros{\'a}rio Fernandes and Susana Borges Furtado}, journal={Linear and Multilinear Algebra}, year={2020}, volume={69}, pages={1255 - 1274} }

We consider the class of symmetric -matrices with zero trace and constant row sums k which can be identified with the class of the adjacency matrices of k-regular undirected graphs. In a previous paper, two partial orders, the Bruhat and the Bruhat-graph order, have been introduced in this class. In fact, when k = 1 or k = 2, it was shown that the two orders coincide, while for the two orders are distinct. In this paper we give general properties of minimal and maximal matrices for these orders…

## 3 Citations

### On the little secondary Bruhat order

- Mathematics
- 2021

Let $R$ and $S$ be two sequences of positive integers in nonincreasing order having the same sum. We denote by ${\cal A}(R,S)$ the class of all $(0,1)$-matrices having row sum vector $R$ and column…

### The Bruhat order on classes of isotopic Latin squares

- MathematicsPortugaliae Mathematica
- 2020

In a previous paper, the authors introduced and studied the Bruhat order in the class of Latin squares of order n. In this paper, we investigate the restriction of the Bruhat order in a class of…

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