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arXiv · 2211.08259

A few words about maps

Robert Cori·Yiting Jiang·Patrice Ossona de Mendez·Pierre Rosenstiehl
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Abstract

In this paper, we survey some properties, encoding, and bijections involving combinatorial maps, double occurrence words, and chord diagrams. We particularly study quasi-trees from a purely combinatorial point of view and derive a topological representation of maps with a given spanning quasi-tree using two fundamental polygons, which extends the representation of planar maps based on the equivalence with bipartite circle graphs. Then, we focus on Depth-First Search trees and their connection with a poset we define on the spanning quasi-trees of a map. We apply the bijections obtained in the first section to the problem of enumerating loopless rooted maps. Finally, we return to the planar case and discuss a decomposition of planar rooted loopless maps and its consequences on planar rooted loopless map enumeration.

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Robert Cori, Yiting Jiang, Patrice Ossona de Mendez, Pierre Rosenstiehl. 2022-11-15. A few words about maps. https://arxiv.org/abs/2211.08259

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