English

The Hopf algebra of generic rectangulations

Combinatorics 2019-03-26 v1

Abstract

A family of permutations called 2-clumped permutations forms a basis for a sub-Hopf algebra of the Malvenuto-Reutenauer Hopf algebra of permutations. The 2-clumped permutations are in bijection with certain decompositions of a square into rectangles, called generic rectangulations. Thus, we can describe the Hopf algebra of 2-clumped permutations using generic rectangulations (we call this isomorphic Hopf algebra the Hopf algebra of generic rectangulations). In this paper, we describe the cover relations in a lattice of generic rectangulations that is a lattice quotient of the right weak order on permutations. We then use this lattice to describe the product and coproduct operations in the Hopf algebra of generic rectangulations.

Keywords

Cite

@article{arxiv.1903.09874,
  title  = {The Hopf algebra of generic rectangulations},
  author = {Emily Meehan},
  journal= {arXiv preprint arXiv:1903.09874},
  year   = {2019}
}