PreLie-decorated hypertrees

Abstract

Weighted hypertrees have been used by C. Jensen, J. McCammond, and J. Meier to compute some Euler characteristics in group theory. We link them to decorated hypertrees and 2-coloured rooted trees. After the enumeration of pointed and non-pointed types of decorated hypertrees, we compute the character for the action of the symmetric group on these hypertrees.

Keywords

• species
• hypertrees
• symmetric group action
• enumerative combinatorics
• [info.info-dm]computer science [cs]/discrete mathematics [cs.dm]