English

Counting rises, levels, and drops in compositions

Combinatorics 2007-05-23 v1

Abstract

A composition of n\NNn\in\NN is an ordered collection of one or more positive integers whose sum is nn. The number of summands is called the number of parts of the composition. A palindromic composition of nn is a composition of nn in which the summands are the same in the given or in reverse order. In this paper we study the generating function for the number of compositions (respectively palindromic compositions) of nn with mm parts in a given set A\NNA\subseteq\NN with respect to the number of rises, levels, and drops. As a consequence, we derive all the previously known results for this kind of problem, as well as many new results.

Keywords

Cite

@article{arxiv.math/0310197,
  title  = {Counting rises, levels, and drops in compositions},
  author = {Silvia Heubach and Toufik Mansour},
  journal= {arXiv preprint arXiv:math/0310197},
  year   = {2007}
}

Comments

22 pages