Enumeration of hypermaps of a given genus

Alain Giorgetti (1) , Timothy R.S. Walsh (2)

1 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)
2 UQAM - Université du Québec à Montréal = University of Québec in Montréal

This paper addresses the enumeration of rooted and unrooted hypermaps of a given genus. For rooted hypermaps the enumeration method consists of considering the more general family of multirooted hypermaps, in which darts other than the root dart are distinguished. We give functional equations for the generating series counting multirooted hypermaps of a given genus by number of darts, vertices, edges, faces and the degrees of the vertices containing the distinguished darts. We solve these equations to get parametric expressions of the generating functions of rooted hypermaps of low genus. We also count unrooted hypermaps of given genus by number of darts, vertices, hyperedges and faces.

Domaines: Cryptographie et sécurité [cs.CR]; Calcul parallèle, distribué et partagé [cs.DC]; Technologies Émergeantes [cs.ET]; Informatique ubiquitaire; Système multi-agents [cs.MA]; Modélisation et simulation; Génie logiciel [cs.SE]

Alain Giorgetti, Timothy R.S. Walsh. Enumeration of hypermaps of a given genus. Ars Mathematica Contemporanea, 2018, 15 (1), pp.225-266. ⟨10.26493/1855-3974.1115.90f⟩. ⟨hal-01948796⟩