Hopf Algebras of Heap Ordered Trees and Permutations

Abstract

It is known that there is a Hopf algebra structure on the vector space with basis all heap-ordered trees. We give a new bialgebra structure on the space with basis all permutations and show that there is a direct bialgebra isomorphism between the Hopf algebra of heap-ordered trees and the bialgebra of permutations.Comment: 10 pages LaTeX, minor revisio