# 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}
}
• Published 7 April 2020
• Mathematics
• Linear and Multilinear Algebra
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

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