Combinatorics of pre-Lie products sharing a Lie bracket

Abstract

We study in detail the operad controlling several pre-Lie algebra structures sharing the same Lie bracket. Specifically, we show that this operad admits a combinatorial description similar to that of Chapoton and Livernet for the pre-Lie operad, and that it has many of the remarkable algebraic properties of the pre-Lie operad.Comment: 40 pages, 9 figure