English

A note on counting labeled and unlabeled trees

Combinatorics 2011-02-01 v2

Abstract

We provide a short combinatorial proof of Cayley's formula by means of a bijective map to an outcome space of an urn-drawing problem. Furthermore we introduce an algebraic structure on the set of labeled trees, which provides a more standard approach to Cayley's formula. Moreover, this algebraic structure sheds light on the problem of counting the unlabeled trees. In particular, it indicates how counting the number of unlabeled trees on nn vertices is connected to finding the number of partitions of n2n-2

Keywords

Cite

@article{arxiv.1012.4654,
  title  = {A note on counting labeled and unlabeled trees},
  author = {Victor N. Ermolaev and Giulio Iacobelli},
  journal= {arXiv preprint arXiv:1012.4654},
  year   = {2011}
}

Comments

This paper has been withdrawn by the author due to a crucial error in counting unlabeled trees

R2 v1 2026-06-21T17:02:26.161Z