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arXiv · 2309.02339

LDP polygons and the number 12 revisited

Ulrike Bücking·Christian Haase·Karin Schaller·Jan-Hendrik de Wiljes
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Abstract

We give a combinatorial proof of a lattice point identity involving a lattice polygon and its dual, generalizing the formula $area(Δ) + area(Δ^*) = 6$ for reflexive $Δ$. The identity is equivalent to the stringy Libgober-Wood identity for toric log del Pezzo surfaces.

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Ulrike Bücking, Christian Haase, Karin Schaller, Jan-Hendrik de Wiljes. 2023-09-05. LDP polygons and the number 12 revisited. https://arxiv.org/abs/2309.02339

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