English

Growth rates of permutation classes: from countable to uncountable

Combinatorics 2019-04-15 v3

Abstract

We establish that there is an algebraic number ξ2.30522\xi\approx 2.30522 such that while there are uncountably many growth rates of permutation classes arbitrarily close to ξ,\xi, there are only countably many less than ξ\xi. Central to the proof are various structural notions regarding generalized grid classes and a new property of permutation classes called concentration. The classification of growth rates up to ξ\xi is completed in a subsequent paper.

Keywords

Cite

@article{arxiv.1605.04297,
  title  = {Growth rates of permutation classes: from countable to uncountable},
  author = {Vincent Vatter},
  journal= {arXiv preprint arXiv:1605.04297},
  year   = {2019}
}

Comments

To appear in Proc. Lond. Math. Soc. (3)