Affiliation:
1. Collège Calvin Geneva 1211 Switzerland
2. Department of Mathematical and Physical Sciences La Trobe University Melbourne 3086 Australia
Abstract
Abstract
This paper studies equable parallelograms whose vertices lie on the Eisenstein lattice. Using Rosenberger’s Theorem on generalised Markov equations, we show that the set of these parallelograms forms naturally an infinite tree, all of whose vertices have degree 4, bar the root which has degree 3. This study naturally complements the authors’ previous study of equable parallelograms whose vertices lie on the integer lattice.
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