English

A counterexample on spectra of zero patterns

Combinatorics 2017-01-06 v2

Abstract

An n×nn\times n zero pattern SS, which is a matrix with entries * and 00, is called spectrally arbitrary with respect to a field FF if any monic polynomial ff of degree nn can be realized as the characteristic polynomial of a matrix obtained from SS by replacing the *'s with non-zero elements of FF. We construct an n×nn\times n zero pattern that is spectrally arbitrary with respect to C\mathbb{C} and has 2n12n-1 nonzero entries.

Keywords

Cite

@article{arxiv.1612.01783,
  title  = {A counterexample on spectra of zero patterns},
  author = {Yaroslav Shitov},
  journal= {arXiv preprint arXiv:1612.01783},
  year   = {2017}
}

Comments

3 pages, a bit stronger result added

R2 v1 2026-06-22T17:14:43.637Z