Simple Relationships Between Lozenge Tiling Functions of Related Regions

TL;DR

This paper derives simple formulas for counting symmetric tilings of hexagons with removed triangles and explores relationships between weighted and unweighted tiling counts, revealing elegant product formulas.

Contribution

It provides explicit formulas for symmetric tilings of complex regions and links weighted and unweighted counts through simple relationships.

Findings

Ratios of symmetric tilings are given by simple product formulas.

Explicit relationships between weighted and unweighted tiling counts.

Formulas apply to regions with arbitrary triangle removals along specific sides.

Abstract

We give a formula for the number of symmetric tilings of hexagons on the triangular lattice with unit triangles removed from arbitrary positions along two non-adjacent non-opposite sides. We show that for certain families of such regions, the ratios of their numbers of symmetric tilings are given by simple product formulas. We also prove that for certain weighted regions which arise when applying Ciucu's Factorization Theorem, the formulas for the weighted and unweighted counts of tilings have a simple explicit relationship.