English

Linear recurrences indexed by $\mathbb{Z}$

Combinatorics 2021-10-12 v2 Rings and Algebras

Abstract

This note considers linear recurrences (also called linear difference equations) in unknowns indexed by the integers. We characterize a unique \emph{reduced} linear recurrence with the same solutions as a given linear recurrence, and construct a \emph{solution matrix} which parametrizes the space of solutions. Several properties of solution matrices are shown, including a combinatorial characterization of bases and dimension of the space of solutions.

Keywords

Cite

@article{arxiv.1906.04311,
  title  = {Linear recurrences indexed by $\mathbb{Z}$},
  author = {Greg Muller},
  journal= {arXiv preprint arXiv:1906.04311},
  year   = {2021}
}

Comments

32 pages, best viewed in color v2) Added sections 9 and 10, containing several results related to twists of matrices

R2 v1 2026-06-23T09:49:35.248Z