English

Inverses of triangular matrices and bipartite graphs

Combinatorics 2013-03-12 v1

Abstract

To a given nonsingular triangular matrix A with entries from a ring, we associate a weighted bipartite graph G(A) and give a combinatorial description of the inverse of A by employing paths in G(A). Under a certain condition, nonsingular triangular matrices A such that A and A^{-1} have the same zero-nonzero pattern are characterized. A combinatorial construction is given to construct outer inverses of the adjacency matrix of a weighted tree.

Keywords

Cite

@article{arxiv.1303.2177,
  title  = {Inverses of triangular matrices and bipartite graphs},
  author = {Ravindra Bapat and Ebrahim Ghorbani},
  journal= {arXiv preprint arXiv:1303.2177},
  year   = {2013}
}

Comments

9 pages

R2 v1 2026-06-21T23:39:13.906Z