English

Isoperimetric Formulas for Hyperbolic Animals

Combinatorics 2022-07-01 v1

Abstract

An animal is a planar shape formed by attaching congruent regular polygons along their edges. In 1976, Harary and Harborth gave closed isoperimetric formulas for Euclidean animals. Here, we provide analogous formulas for hyperbolic animals. We do this by proving a connection between Sturmian words and the parameters of a discrete analogue of balls in the graph determined by hyperbolic tessellations. This reveals a complexity in hyperbolic animals that is not present in Euclidean animals.

Keywords

Cite

@article{arxiv.2206.14910,
  title  = {Isoperimetric Formulas for Hyperbolic Animals},
  author = {Erika Roldan and Rosemberg Toala-Enriquez},
  journal= {arXiv preprint arXiv:2206.14910},
  year   = {2022}
}

Comments

16 pages, 2 figures, 3 tables

R2 v1 2026-06-24T12:08:55.697Z