English

A note on Pr\"ufer-like coding and counting forests of uniform hypertrees

Discrete Mathematics 2011-10-04 v1

Abstract

This note presents an encoding and a decoding algorithms for a forest of (labelled) rooted uniform hypertrees and hypercycles in linear time, by using as few as n2n - 2 integers in the range [1,n][1,n]. It is a simple extension of the classical Pr\"{u}fer code for (labelled) rooted trees to an encoding for forests of (labelled) rooted uniform hypertrees and hypercycles, which allows to count them up according to their number of vertices, hyperedges and hypertrees. In passing, we also find Cayley's formula for the number of (labelled) rooted trees as well as its generalisation to the number of hypercycles found by Selivanov in the early 70's.

Keywords

Cite

@article{arxiv.1110.0204,
  title  = {A note on Pr\"ufer-like coding and counting forests of uniform hypertrees},
  author = {Christian Lavault},
  journal= {arXiv preprint arXiv:1110.0204},
  year   = {2011}
}

Comments

Version 2; 8th International Conference on Computer Science and Information Technologies (CSIT 2011), Erevan : Armenia (2011)

R2 v1 2026-06-21T19:13:53.102Z