Enumération des 2-arbres k-gonaux

  • Gilbert Labelle
  • Cédric Lamathe
  • Pierre Leroux
Conference paper
Part of the Trends in Mathematics book series (TM)


In this paper1, we generalize 2-trees by replacing triangles by quadrilaterals, pentagons or k-sided polygons (k-gons), where k ≥ 3 is given. This generalization, to k-gonal 2-trees, is natural and is closely related, in the planar case, to some specializations of the cell-growth problem. Our goal is the enumeration, labelled and unlabelled, of k-gonal 2-trees according to the number n of k-gons. Wegive explicit formulas in the labelled case, and, in the unlabelled case, recursive and asymptotic formulas.


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Copyright information

© Springer Basel AG 2002

Authors and Affiliations

  • Gilbert Labelle
    • 1
  • Cédric Lamathe
    • 1
  • Pierre Leroux
    • 1
  1. 1.LaCIMUniversité du Québec àMontréalMontréalCanada

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