English

Well quasi-orders arising from finite ordered semigroups

Formal Languages and Automata Theory 2022-03-15 v1

Abstract

In 1985, Bucher, Ehrenfeucht and Haussler studied derivation relations associated with a given set of context-free rules. Their research motivated a question regarding homomorphisms from the semigroup of all words onto a finite ordered semigroup. The question is which of these homomorphisms induce a well quasi-order on the set of all words. We show that this problem is decidable and the answer does not depend on the homomorphism, but it is a property of the ordered semigroup.

Cite

@article{arxiv.2203.06535,
  title  = {Well quasi-orders arising from finite ordered semigroups},
  author = {Ondřej Klíma and Jonatan Kolegar},
  journal= {arXiv preprint arXiv:2203.06535},
  year   = {2022}
}
R2 v1 2026-06-24T10:11:13.113Z